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Abstract

Anticoagulant rodenticides (ARs) are widely used to control rodents. A method based on online turbulent flow chromatography (TFC) combined with LC-MS/MS has been established for rapid quantitative determination of eight ARs in human blood and urine. This method, which does not require time-consuming pre-processing steps, renders it especially suited for use in emergency poisoning cases. Sample preparation, including extraction, centrifugation, and filtration, was followed by online clean-up using TFC. The total run-time was within 13.5 min, including online purification, chromatographic separation, and re-equilibration of the TFC system. The parameters for sample extraction, purification, separation, and detection in this study were optimized separately. The linear regression coefficients of matrix-matched calibration standard curves established for quantification were greater than 0.9976. The limit of quantification (LOQ) for the method were found to be 0.3–3.0 ng/mL in human blood and 0.06–0.6 ng/mL in urine. The recoveries of spiked target compounds at different concentrations in human blood and urine were 91.8–111.9% and 86.9–105.3%, respectively. Inter- and intra-day precision values were both less than 12.5%, and the matrix effects of human blood and urine samples for ARs were 75.3–108.6% and 102.7–130.0%, respectively. This method had successfully applied to the emergency detection of ARs in biological samples of poisoned patients.

Open access

Abstract

This study describes the development of a method allowing the simultaneous separation and quantification of five statins by High performance liquid chromatography/Diode Array Detector (HPLC/DAD). Optimization was accomplished using chemometric tools such as the Design Space (DS) and Response Surface Methodology (RSM). Central Composite Design (CCD) and DS were applied for the optimization of the chromatographic procedure as well as the robustness of the chromatographic method by taking the ratio of the percentage of acetonitrile (%ACN) Buffer solution, the pH and the mobile phase flow rate as critical parameters. Satisfactory results were obtained after the optimization phase with a percentage of mobile phase equal to 46.19%, a pH of 4.16 and the flow rate is 1.4 mL min−1 by setting the resolution limits above 6, and the target retention time of 20 min. Using the DS and CCD approach, we have developed a robust and reliable procedure for the simultaneous and accurate separation and quantification of the five statins.

Open access

Abstract

Although glimepiride (GLM) is the first-line treatment of Type II diabetes, low extraction recovery is still a significant limitation in previous plasma analysis methods. An optimized solid-phase extraction method of GLM in human plasma with excellent extraction recovery, 100 ± 0.06%, was achieved using liquid chromatography-electrospray ionization tandem mass spectrometry and Gliclazide (GLZ) as an internal standard. GLM was extracted from 100 µL plasma sample using Sep-Pak® vac 1cc (100 mg) C18 column and methylene chloride: methanol (2: 1, v/v) as eluant. Both GLM and GLZ were monitored by a triple quad mass spectrometer applying positive multiple reaction monitoring mode (+MRM). The protonated precursor ions and product ions of GLM and GLZ were m/z 491(352), and m/z 324 (127), respectively. The detection and measurement of low levels of GLM in human plasma reached to picogram range (limit of detection (LOD) = 60 pg/mL, limit of quantification (LOQ) = 200 pg/mL). The method was validated in terms of selectivity, linearity, recovery, accuracy, and precision. The method was successfully applied to the pharmacokinetic study of GLM following oral administration of 1 mg GLM tablets to 12 healthy volunteers.

Open access

Abstract

In the experiments, the sound generated during the breaking of chocolate samples was examined. The fracture was performed by a precision penetrometer, the breaking sound was recorded. Texture index (TI) was calculated from the resulting signal. First the change of the resulting TI was monitored as a function of the samples' temperature. The sample groups of the same dark chocolate with different temperatures were completely separated from each other with statistical tool (LDA, linear discriminant analyses), but no trend was found to describe the change. Secondly, based on the TI, we could identify and classify the chocolate samples in the appropriate groups (based on cocoa content from 40 to 85%). According to linear discriminant analyses chocolates with different cocoa content were completely separated and showed a certain pattern. Based on the obtained results, it can be stated that the cocoa content of chocolate can be determined on the basis of TI obtained by acoustic method.

Open access

Abstract

Grapevine berry shape has important marketing value in the table grape commerce, hence variability evaluation of this characteristic is highly important. In this study berry shape of 5 table grape genotypes: “Fanny”, “Lidi”, “Hamburgi muskotály”, “Moldova”, and “Orsi” were compared. To evaluate the shape variability graphic reconstruction and elliptic Fourier analysis have been carried out. Shape outlines have been investigated and Principal Component Analysis (PCA) has been performed with the SHAPE software package. PCA of the contours showed that 6 out of the 77 principal components were effective to describe shape attributes. The first 6 PCs explained 94.51% of the total variance. PC1 associated with the width and length of the berry. PC2 related to the shape of the top and bottom of the berries, while PC3 linked to the ratio of the top and the bottom width. ANOVA of the principal component scores revealed significant difference among the genotypes. Results suggest that morphology of the berry is a variable not only among but within the accessions. Our findings confirmed that elliptic Fourier descriptors (EFDs) would be a powerful tool for quantifying grapevine berry morphological diversity.

Open access

Abstract

The engineering application's design process starts with a concept, based on our theoretical knowledge and continues with a numerical simulation. In our paper, we review the finite volume method (FVM) which is used generally for heat and fluid dynamic simulations.

We compare three different computational fluid dynamics (CFD) software (based in the fine volume method) for validating a NACA airfoil, which can be used for example in the aerospace industry for an airplane's wing profile, and it can be used for example in the renewable industry for a wind turbine's blade or a water turbine's impeller profile. At the end of this paper, the result of our simulations will be compared with a validation case and the difference between the CFD software and the measured data will be presented.

Open access

Abstract

This research aims to determine whether the treatment of food products in a microwave electromagnetic field is advantageous or disadvantageous compared to conventional technologies. In household practice, microwave energy transfer is used mostly for heating. One of the most important tangible benefits of microwave heat treatment is that it causes less damage to the nutritional value of the product due to its speed.

Despite the fact that microwave technology was introduced more than 70 years ago, it is still not clear whether its application results in equivalent products in terms of quality and food safety.

This study demonstrates how heat-treated wines with microwave energy transmission and with convective heating in a thermostatic water bath are affected. In the white, rose and red wine samples pasteurized at a temperature of 74 ± 0.5 °C, significant differences between the two heating methods regarding colour characteristics could be indicated.

Open access

Abstract

Industrial wastewater is a growing environmental challenge due to its high concentrations of organics and its limited biological degradability. Up to date, however, no published work discussed industrial wastewater characterization, which is the focus of this study. Moreover, the effect of hydrothermal treatment on the chemical oxygen demand (COD) removal and the soluble chemical oxygen demand (SCOD) release was investigated in this work. Wastewater samples were collected from different industrial sites and characterized in order to determine their initial properties. It was summarized that the salinity of wastewater estimated by EC was relatively low, and its pH values were in the acceptable range. On the other hand, however, high values of sodium absorption ratio (SAR) were obtained in all samples post to hydrothermal treatment. Nonetheless, our results revealed higher SCOD release post to hydrothermal treatment suggesting better efficiency of COD removal obtained by this treatment technique.

Open access

Abstract

In milling industry, the object of milling is to separate endosperm and bran parts of wheat, and to recover flour. The most important and the highest energy requirement operation is grinding. The quantity and quality of flour depends on: the variety of wheat that will be milled, the type of grinding equipment and the condition used before the grinding. During our experiments two different grain structured varieties of wheat were milled in laboratory conditions with disk, stone grinder and roller miller in air-dry, and conditioned states. The performance of the equipment and the particle size distribution (PSD) of the produced grist were measured, then the energy requirements of the grinders were calculated. In the milling experiments the ash contents of the different particle sized fractions were compared to map particular properties of wheat cultivars.

Open access
Progress in Agricultural Engineering Sciences
Authors: Tamás Zsom, Petra Polgári, Lien Phuong Le Nguyen, Géza Hitka and Viktória Zsom-Muha

Abstract

Broccoli's high perishability and its sensitivity to negative quality changes (i.e., mass loss, ethylene induced degreening, abscission of leaves, and florets) generates quality problems during postharvest. Freshly harvested samples were stored at 5 and 21 °C after separately treated for 24 h with 625 ppb 1-methyl-cyclopropene (1-MCP), 24 h with 2 ppm ethylene and 1-MCP followed by ethylene. Quality maintenance effectivity of 1-MCP was investigated during cold and room storage by non-destructive optical methods (chlorophyll fluorescence and DA-index®) and by the evaluation of the visual physiological symptoms. The highly positive effects of 1-MCP treatment combined with cold storage were obviously proven on quality maintenance providing better retention of initial quality related to the initial mature green stage as chlorophyll content related DA-index®; F m, F v, F v/F m, and F m/F 0 chlorophyll fluorescence values. From the practical point of view, the rapid, and easy-to-use Sintéleia FRM01-F Vis/NIR DA-meter® could be applied relatively easy for the quality measurement of broccoli. The reproducibility of quality determination could be increased by the enhanced number of measuring points or using computer aided imaging methods (i.e., chlorophyll fluorescence imaging, machine vision system) providing global and more reliable information about quality changes.

Open access

Abstract

Liensinine is a bisbenzyltetrahydroisoquinoline alkaloid extracted from lotus (Nelumbo nucifera GAERTNER., Nelumbonaceae), especially in its embryo loti “Lien Tze Hsin” (green embryo of mature seed). A rapid and simple UPLC-MS/MS method was developed to determine liensinine in mouse blood and its application to a pharmacokinetic study. The blood samples were preprocessed by protein precipitation using acetonitrile. Midazolam (internal standard, IS) and liensinine were gradient eluted by mobile phase of methanol and water (0.1% formic acid) in a Waters UPLC BEH C18 column. The multiple reaction monitoring of m/z 611.3 → 206.1 for liensinine and m/z 326.2 → 291.1 for IS with an electrospray ionization (ESI) source was used for quantitative detection. The calibration curve ranged from 0.5 to 400 ng/mL (r > 0.995). The accuracy ranged from 92.2 to 108.2%, the precision of intra-day and inter-day was less than 14%, and the matrix effect was between 100.0% and 109.6%, the recovery was better than 71.0%. The developed UPLC-MS/MS method was successfully used for a pharmacokinetic study of liensinine in mice after oral (5 mg/kg) and intravenous administration (1 mg/kg), and the absolute availability of liensinine was 1.8%.

Open access

Abstract

A highly sensitive high-performance liquid chromatography (HPLC) method was developed for the simultaneous determination of eight biogenic amines in aquatic products. The biogenic amines in the sample were extracted with 5% trichloroacetic acid, derived with dansyl chloride (Dns-Cl) and quantified by a UV detector. The results showed that tryptamine (TRY), 2-phenethylamine (PHE), putrescine (PUT), cadaverine (CAD), histamine (HIS), tyramine (TPY), spermidine (SPD), and spermine (SPM) were effectively separated in 18 min in the range of 0.1–50 mg/kg with a good linear coefficient (r 2 > 0.999). The detection limits (LODs) of the eight biogenic amines were 0.007–0.021 mg/kg while the limits of quantification (LOQs) were 0.024–0.069 mg/kg with the recoveries basically between 68 and 123%. The determination of eight biogenic amines in five commercial fermented aquatic products indicating that the developed method could be applied for the simultaneous detection of biogenic amines in multiple aquatic products.

Open access
Progress in Agricultural Engineering Sciences
Authors: Judit Perjéssy, Ferenc Hegyi, Magdolna Nagy-Gasztonyi, Rita Tömösközi-Farkas and Zsolt Zalán

Abstract

Nowadays, demand for products which beyond the overall nutritional value have a feature that protects the consumer health, have increased. Several studies have proved that fruit juices can become a suitable carrier or medium for probiotic organisms. Therefore, the aim of our study was to investigate the possibility of the probiotication of sour cherry juice (SCJ) by fermentation with probiotic starter culture. During the fermentation 9 Lactobacillus strains were used and Újfehértói fürtös sour cherry species as raw material. To reach the recommended probiotic cell count we investigated the pH adjustment, supplementation of nutrients, the effect of dilution, and strain adaptation to SCJ. In our study the properties of the strains – such as reproduction and metabolism – and its effect on the raw material were investigated. A significant difference was observed between the number of viable cells of certain Lactobacillus strains, that is important in point of view of the development of probiotic-containing products. Furthermore, the lactic acid fermented SCJ can enhance the polyphenol content and antioxidant activity to promote the health of consumers.

Open access

Abstract

Similarly to other industries wineries also increasingly attempt to minimize and utilize waste to protect our environment. The aim of this study was to determine the optimal parameters (temperature, solvent concentration, and time) of extracting total polyphenol content (TPC) from Tokaji Aszú marc using two different extraction solvents: ethanol–water and isopropanol–water (1:4 solid/liquid ratio). The extractions were achieved based on Central Composite Design with Response Surface Method (CCRD–RSM). The optimal extraction parameters in the case of ethanol–water solvent: 60 °C temperature, 59.5% ethanol concentration in solvent, 5 h. At these parameters the probable TPC concentration is 23966.2 uM GAE/L. The optimal extraction parameters in the case of isopropanol–water solvent: 60 °C temperature, 52% ethanol concentration in solvent, 5 h. At these parameters the probable TPC concentration is 7188.44 uM GAE/L. In both cases the binary solvent was better than the mono-solvent. Ethanol–water solvent was more efficient than the isopropanol–water solvent.

Open access

Abstract

An ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC–MS/MS) method was developed to determine the fenofibric acid (FA) in human plasma and applied to a pharmacokinetic study of fenofibrate tablet (Lipanthyl® supra, 160 mg) on Chinese subjects which had not been reported. Bezafibrate was used as an internal standard (IS), and the plasma samples were precipitated by methanol. Multiple reaction monitoring (MRM) mode was used to quantitatively analyzed FA m/z 317.2 → 230.7 and the IS m/z 360.0 → 274.0 in the electrospray ionization (ESI) negative interface. The calibration curves were linear over the range of 50–30,000  ng/mL (r 2  ≥  0.996). The intra-day and inter-day precision (coefficient of variation, CV%) was less than 2.7 and 2.5%, respectively. The accuracy (relative error, RE%) ranged from −4.5 to 6.9%. The average recovery was higher than 86.2%, and the matrix effect was between 95.32 and 110.55%. The simple, rapid, and selectivity method was successfully applied to the pharmacokinetic study of fenofibrate tablets on Chinese subjects.

Open access

Summary

In this study, single-walled carbon nanotubes (SWNTs) were used to determine organochlorine pesticides (chlorothalonil and pentachloronitrobenzene) in water using dispersive solid-phase extraction (DSPE), followed by gas chromatography (GC). The optimal adsorption conditions were determined by analyzing the effect of adsorbent dosage, adsorption time, eluent type and volume, and elution time. Under the optimal conditions, a good linearity was obtained at concentrations from 10 to 400 μg L−1 with correlation coefficients ranging from 0.9991 to 0.9986. The limits of detection (LOD) for the two organochlorine pesticides were 0.025 and 0.049 μg L−1, and the limits of quantification (LOQ) were 0.080 and 0.156 μg L−1, respectively. The accuracy of the proposed method was evaluated by measuring the recovery of the spiked samples, which ranged from 82.5% to 110.5% at spiking levels of 0.5–10 μg L−1 with relative standard deviations lower than 5.6% (n = 6). This method was successfully applied to determine the target analytes in canal water, drinking water, and water taken from the inlets and outlets of a wastewater treatment plant. The results demonstrate that the developed method has great potential for determining the two organochlorine pesticides in water samples.

Open access
Progress in Agricultural Engineering Sciences
Authors: Mai Sao Dam, Lien Le Phuong Nguyen, Tamás Zsom, Géza Hitka, Ildikó Csilla Zeke and László Friedrich

Abstract

The aim of this work was to evaluate the effect of packaging perforation on quality of carrot slices during cold storage at 5 °C. Polyethylene bags with different number of perforations (3, 4, and 6) were used in this experiment. Headspace oxygen concentration, respiration, weight loss, surface color, firmness, pH, and soluble solid content were examined throughout storage. It was observed, that all the investigated packaging were effective in maintaining the quality of carrot slices compared to the control. There was no symptom of decay until 12 days. In addition, pH, soluble solid content, and firmness showed nonsignificant change. Moreover, weight loss of packed carrot slices was below 2% after 12 days of storage. Packed carrot had better appearance at the end of experiment (12 days) than that of control.

Open access

Abstract

Agricultural production is threatened by different invasive species, as their damage results in a serious loss of income. The aim of the research was the assessment of the swarming dynamics and damage of the western corn rootworm (WCR) adults and larvae. The experiment was carried out in monoculture fertilization long-term experiments and three maize hybrids compared for their reaction against WCR adult and larval damage under non-infested plots at different nitrogen levels. Differences among the hybrids have a lower effect on the damage of corn rootworm adults and larvae than the amount of applied nitrogen. The phosphorus-potassium are optimal levels, while nitrogen ranges from 0 to 300 kg and no nutrient supply took place in the control plots for 30 years. The number of adults located and feeding on the styles of the female flower recorded and the damage caused on the roots by larvae ranked on a modified Iowa scale. Nitrogen fertilization resulted in a change in the silking time. The lowest root damage observed in the case of the high nutrient treatment with an Iowa value of 3.18. The coincidence of the nourishment of adults and the egg-laying time with silking is a potential threat in terms of fertility. Based on the results, it found that the extent of root damage can be reduced through the optimal selection of the time and dose of nutrient supply, primarily that of nitrogen. In general, both larvae and adults can cause severe yield loss, but the method of control against them is different. The coincidence of the nourishment of adults and the egg-laying time with silking is a potential threat in terms of fertility.

Open access

Abstract

Th accurate rapid, simple and selective reversed phase high performance liquid chromatography (RP-HPLC) has been established and validated for the determination of captopril (CAP). Chromatographic separation was accomplished using prepacked ODSI C18 column (250 mm × 4.6 mm with 5 μm particle size) in isocratic mode, with mobile phase consisting of water: acetonitrile (60:40 v/v), pH adjusted to 2.5 by using 85% orthophosphoric acid at a flow rate of 1 mL/min and UV detection was performed at 203 nm. RP-HPLC method used for the analysis of CAP in mobile phase and rabbit plasma was established and validated as per ICH-guidelines. It was carried out on a well-defined chromatographic peak of CAP was established with a retention time of 4.9 min and tailing factor of 1.871. The liquid–liquid extraction method was used for extraction of CAP from the plasma. Excellent linearity (R 2 = 0.999) was shown over range 3.125–100 µg/mL with mean percentage recoveries ranges from 97 to 100.6%. Parameters of precision and accuracy of the developed method meet the established criteria. Intra and inter-day precision (% relative standard deviation) study was also performed which was less than 2% which indicate good reproducibility of the method. The limit of detection (LOD) and quantification for the CAP in plasma were 3.10 and 9.13 ng/mL respectively. The method was suitably validated and successfully applied to the determination of CAP in rabbit plasma samples.

Open access

Abstract

Tricarboxylic acid cycle is an important pathway and the metabolites of tricarboxylic acid cycle, simple organic acids, play important roles in many physiological processes. The new conditions of high performance liquid chromatography (HPLC) with improved separation selectivity were developed and optimized by choosing suitable store solvent, methanol, which can catalyze the reaction, aldol condensation, and facilitate the formation of new compound to improve simultaneous detection of nine metabolites of tricarboxylic acid cycle, including lactic acid, pyruvic acid, citric acid, alpha-ketoglutaric acid, malic acid, succinic acid, cis-aconitic acid, itaconic acid, and fumaric acid, and be applied in analysis of the nine metabolites in psoriasis mice skin. This study shows that in process of developing methods, expect conventional chromatographic condition, solvent should also be considered carefully.

Open access

Abstract

During the process of fermentation, the chemical compositions of trifoliate orange (Poncirus trifoliate (L). Raf) changed greatly. To provide a completely phytochemical profile, high-performance liquid chromatography-diode array detector-hyphenated with tandem mass spectrometry (HPLC–DAD–ESI-MS/MS) has been successfully applied to screen and identify the unknown constituents of trifoliate orange during fermentation, which make it available for the quality control of fermented products. Multivariate statistical analysis was performed to classify the trifoliate oranges based on the status of fermentation. A total of 8 components were identified among the samples. Hierarchical Clustering Analysis (HCA) and Principal Component Analysis (PCA) demonstrated the fermented and unfermented trifoliate oranges were obviously different, an effective and reliable Partial Least Square Discriminate Analysis (PLS-DA) technique was more suitable to provide accurate discrimination of test samples based their different chemical patterns. Furthermore, a permutation validated the reliability of PLS-DA and variable importance plot revealed that the characterized syringing, naringin, and poncirin showed the high ability to distinguish the trifoliate oranges during fermentation. The present investigation could provide detailed information for the quality control and evaluation of trifoliate oranges during the fermentation process.

Open access

Abstract

Carbofuran is a carbamate pesticide, a broad-spectrum, high-efficiency, low-residue, and highly toxic insecticide, acaricide, and nematicide, widely used in agriculture. Carbofuran is most harmful to birds, and birds or insects killed by furan poisoning can be killed by secondary poisoning after being foraged by raptors, small mammals, or reptiles. In this paper, an UPLC-MS/MS method was developed for the determination of carbofuran and its metabolite, 3-hydroxycarbofuran, in duck liver. Liver tissue was first ground into a homogenate and then passed through ethyl acetate liquid-liquid extraction processing samples. Multiple reaction monitoring (MRM) mode was used for quantitative analysis, m/z 222.1 → 165.1 for carbofuran, m/z 238.1 → 180.9 for 3-hydroxycarbofuran and m/z 290.2 → 198.2 for an internal standard. The standard curves of carbofuran and 3-hydroxycarbofuran in duck liver were within a range of 2–2000 ng/g, where the linearity was good, the lower limit of quantification was 2 ng/g. The intra-day precision of carbofuran and 3-hydroxycarbofuran was <14%, and the inter-day precision was <13%, the accuracy range was between 91.8 and 108.9%, the average extraction efficiency was higher than 75.1% with a matrix effect between 93.4 and 107.7%. The developed method was applied to a situation of suspected duck poisoning at a local farm.

Open access

Abstract

A simple and sensitive liquid chromatography-mass spectrometric (LC-MS) method has been developed and validated for the simultaneous determination of ezetimibe (EZE), atorvastatin calcium (ATO), and simvastatin (SMV) in combined dosage forms and human plasma. Successful separation of the studied drugs was achieved on a Zorbax Eclipse Plus C18 column (3.0 × 150 mm, 5 µm) using a mobile phase consisting of acetonitrile and 0.1% formic acid in water (65:35, v/v) at a flow rate of 0.5 mL min−1. Total run time was 9.3 min and diclofenac sodium was used as internal standard (IS). Positive selected ion monitoring (SIM) mode was applied where, the monitored ions were those at m/z values of 392.1, 559.3, 296.0, and 441.4 corresponding to EZE, ATO, IS, and SMV, respectively. The method was fully validated according to the ICH guidelines. The intraday and interday precision showed relative SD values not more than 1.77 and 1.99%; respectively. The limits of detection (LOD) were 0.25, 0.25, and 0.75 ng mL−1 while the limits of quantification (LOQ) were 1.25, 0.75, and 2.5 ng mL−1 for EZE, ATO, and SMV, respectively. The developed method was applied on two types of combined tablets concerning drug assay with mean percent recoveries within acceptable range. The method has been extended to the determination of the studied drugs in human plasma where, a solid phase extraction method was optimized for their extraction with percent recovery not less than 97%.

Open access

Abstract

A sweeping micellar electrokinetic chromatography (sweeping-MEKC) enrichment model was established for the determination of three chlorophenols (CPs) in cosmetics, namely, bithionol, pentachlorophenol (PCP), and 2,4,6-trichlorophenol (2,4,6-TCP). The optimum electrophoretic conditions were 20 mM NaH2PO4-80 mM sodium dodecyl sulfate (SDS) and 30% (v/v) acetonitrile (pH 2.3). The optimum on-line concentration conditions were as follows: sample matrix, 100 mM NaH2PO4; pressure injection at 20.67 kPa (3 psi) for 25 s. The linear range of bithionol, PCP, and 2,4,6-TCP are 0.20–4.00 μg mL−1, 0.10–2.00 μg mL−1, and 0.05–2.00 μg mL−1 respectively, with correlation coefficient (r) over 0.9972. The limits of detection (LOD) based on three times the signal-to-noise ratio (S/N = 3) are in the range of 0.0061–0.024 μg mL−1. Recoveries for the three CPs in powder and lotion samples are between 79.7 and 110.2% with relative standard deviation (RSD) of 1.38–5.54% and 92.2–121.3% with RSD of 0.72–6.09%, respectively. The proposed method can provide reference for the determination of trace CPs in different sample matrix.

Open access

Abstract

This study focused on developing an effective and environmentally friendly method to measure ligustrazine in rat serum by using polymer monolith micro-extraction (PMME) technique. A poly (methacrylic acid-ethylene glycol dimethacrylate) material was used to extract ligustrazine through hydrophobic and ion-exchange interaction. Qualitative and quantitative analysis was performed by a liquid chromatography and tandem mass spectrometry. After optimization of several PMME conditions, the developed method exhibited excellent extraction performance to the ligustrazine. Good linearity was acquired ranging from 10 to 2,000 ng mL−1, and the limit of detection of the proposed method was 0.14 ng mL−1. The recoveries measured by spiking three different concentrations in rat serum ranged from 82.6 to 95.3%, and excellent precision was found with relative standard deviations (RSDs) less than 8.3% for intra-day and 9.7% for inter-day, respectively. At last, the applicability of the method was further confirmed through continuous monitoring of ligustrazine in rat serum after dosing of ligustrazine tablets to rats.

Open access

Abstract

Electronic nicotine delivery systems (ENDs) are gaining popularity in Jordan as alternatives to tobacco cigarettes with an estimation of 10% of tobacco smokers switching to ENDs. Since nicotine is toxic and highly addictive substance, it is important to develop and validate an easy and rapid analytical method to accurately measure nicotine level in e-liquids. A simple high performance liquid chromatography–photodiode array detection (HPLC–PDA) method was developed and validated for rapid determination of the actual nicotine content in 11 of the most popular e-liquids brands available in the Jordanian market and compared to the nicotine levels appeared in the labeled packaging. The new method of analysis showed an excellent linearity with correlation factor equal to 0.9994 with analytical range between 100 and 1,000 µg/mL, and Limit of detection (LOD) and Limit of quantification (LOQ) of 32.6 µg/mL and 98.9 µg/mL, respectively. The results showed that the actual measured nicotine concentrations ranged from 0 to 25.81 mg/mL with percent deviation ranged from 63.1% less than to 3.24% more than the labeled concentration on packaging. And more than 10% deviation difference in actual nicotine concentrations versus labeled were found in 9 of the 11 e-liquid products (82%). In conclusion, nicotine labelling among e-liquids products have not accurately reflect the actual content which may have potential negative impact on users.

Open access

Abstract

Chloroquine phosphate (CQ) the antimalarial drug and suggested to treat the pandemic disease coronavirus (COVID-19) is often adulterated with some of the non-steroidal anti-inflammatory drugs (NSAIDs) such as paracetamol, aspirin (ASP), or both. The purpose of this study is to detect such counterfeited drugs, using a reversed phase high pressure liquid chromatography (RP-HPLC) method with fluorescence detection. Analysis was divided into three phases. In the first phase, a Plackett-Burman design (PBD) was used to screen five independent factors, namely, buffer pH, buffer concentration (mM), acetonitrile content (%), flow rate (mL/min) and triethylamine (TEA) content in the buffer preparation (%). The selected dependent variables were (resolution, symmetry of peaks and run time). The objective of the second phase was to optimize the method performance using Box-Behnken design (BBD) and desirability function for multiple response optimization to obtain the best chromatographic performance with the shortest run time. Optimal chromatographic separation was achieved on a YMC-pack pro C18 ODS-A column (15 cm × 4.6 mm, 5 µm) at room temperature The optimum mobile phase consisted of acetonitrile and 5 mM sodium dihydrogen phosphate buffer containing 0.5% triethyamine (30:70, v/v) with the pH adjusted to 3.5 using an orthophosphoric acid solution. The flow rate was maintained at 1 mL/min, and the detection was performed with a fluorescence detector fixed at 380 nm (λemission) after excitation at 335 nm (λexcitation). The third phase was method validation according to ICH guidelines, providing to be specific, precise, accurate, and robust. The method is linear over a range of 0.4–8 µg/mL for chloroquine and ASP, while for paracetamol it is linear over 16–48 µg/mL. The developed RP-HPLC method was used for quantitation of the three drugs in chloroquine dosage form samples. The method shows a great tendency in the classification between the genuine chloroquine and the adulterated ones in pharmaceutical preparations and breast milk.

Open access

Abstract

Objective

To determine the levels of gallic acid and ellagic acid by using high-performance liquid chromatography (HPLC) with R software hierarchical cluster analysisin Elaeagnus angustifolia L. gathered from different locations in Xinjiang.

Methods

A chromatographic column Diamonsil C18 with a size of 4.6 × 250 mm and 5 μm was used with methanol as A and 0.1% phosphoric acid aqueous solution as B as the mobile phase. The flow rate was 1 mL/min for the gradient elution and the injection volume was 5 μL. HPLC was performed with a detection wavelength of 260 nm and chromatographic column of 35 °C. In addition, R software hierarchical clustering method was used for studying the levels of gallic acid and ellagic acid in E. angustifolia L. from 10 areas.

Results

Gallic acid and ellagic acid showed a good linear relationship between 7.375 and 236 μg/mL with a correlation coefficient of 0.9999, and between 3.625 and 116 μg/mL with a correlation coefficient of 0.9999 respectively. The average recovery values were 103.98 and 101.57%, and the Relative Standard Deviation (RSD) values were 1.92 and 1.47%.

Conclusion

Differences in the levels of gallic acid and ellagic acid in E. angustifolia L. leaves from different areas in Xinjiang showed that both were the highest in Kuitun.

Open access
Acta Chromatographica
Authors: Xiaoyan Zhang, Jie Liu, Wenbo Sun, Xiangchun Shen, Xiaojian Gong, Cong Wang, Yan Liang and Wei Zhou

Abstract

Natural hemostatic compounds from Toddalia asiatica (Linn) Lam (T. asiatica) root bark had been investigated by a novel strategy, chemical fingerprint–pharmacokinetic–pharmacodynamic (CF–PK–PD) for the first time in this study. The extract sample of T. asiatica root bark was subdivided into petroleum ether (PE), ethyl acetate (EA) and n-butanol (n-B) sample by reagent extraction, EA sample showed significant hemostatic activity using prothrombin time (PT), activated partial thromboplastin time (APTT) and fibrinogen (FIB) as evaluation indexes from rat plasma of PK experiment in hemorrhagic rat model. CF analysis was adopted to assist us to discover six natural compounds from T. asiatica root bark in actual rat plasma after sample treatment by Ultra Performance Liquid Chromatography-Electrospray Ionization (UPLC-ESI) MS, there were only lomatin and 5-methoxy-8-hydroxy psoralen showing significant hemostatic effect (P < 0.05) mainly through endogenous coagulation pathway and fibrinolytic system. In PK–PD study, six compounds in EA sample exhibited relatively rapid absorption and slow elimination characteristics. The mean T max and t 1/2β of isopimpinellin and pimpinellin were 1.74 and 0.59 h, 5.31 and 6.89 h in rats. On the basis of Sigmoid–E max model, PK–PD related curves of FIB in hemorrhagic rat model after treatment of T. asiatica root bark were obtained. Predicted E max, EC 50 and k e0 of FIB under isopimpinellin were 4.87 mg/mL, 1.39 μg/mL and 0.81 1/h; predicted E max, EC 50 and k e0 of FIB under pimpinellin were 4.29 mg/mL, 2.47 μg/mL and 0.77 1/h. In conclusion, hemostatic compounds from T. asiatica root bark had been materialized, there were lomatin, isopimpinellin, pimpinellin and 5-methoxy-8-hydroxy psoralen at least as its main active substances through coagulation pathways and fibrinolytic system. CF–PK–PD method as a promising method was worthy of follow-up opening, application in pharmaceutical research.

Open access

Abstract

Sarecycline is a narrow-spectrum antibiotic for the treatment of acne, which is a chronic inflammatory disease of the hair follicle sebaceous glands. In the study, UPLC-MS/MS was used to establish a rapid and accurate analytical method. The sarecycline was determined with poziotinib as internal standard (IS) in rat plasma. An ACQUITY UPLC HSS T3 column (2.1 × 100 mm, 1.8 μm) could performe chromatographic separation with the mobile phase (methanol: water of 0.1% formic acid) with gradient elution. The ions of target fragment were m/z 488.19→410.14 for sarecycline and m/z 492.06→354.55 for poziotinib, which could quantify the electrospray ionization of positive multiple reaction monitoring (MRM) mode. The linear calibration curve of the concentration range was 1–1,000 ng/mL for sarecycline with a lower limit of quantification (LLOQ) of 1 ng/mL. The mean recovery was between 82.46 and 95.85% for sarecycline and poziotinib in rat plasma. RSD for precision of inter-day and intra-day were between 3.24 and 13.36%, and the accuracy ranged from 105.26 to 109.75%. The developed and validated method was perfectly used in the pharmacokinetic study and bioavailability of sarecycline after intravenous and oral administration in rats.

Open access
Progress in Agricultural Engineering Sciences
Authors: Aidin Pahlavan, Mohammad Hassan Kamani, Amir Hossein Elhamirad, Zahra Sheikholeslami, Mohammad Armin and Hanieh Amani

Abstract

This study was focused on the assessment of relationships among the properties of wheat and their resultant flour, dough and final bread. For this purpose, multivariate linear regression in the form of the step-wise algorithm was applied to evaluate the relation among the flour characteristics of wheat with quality of dough and the final breads (Barbari and Lavash). The results showed that variety of wheat (Orum, Pishgam, and Zareh) could not affect the moisture content and quantity of the flour residue; however, considerable variation was observed on protein content and Zeleny number. The multivariate regression analysis built appropriate models to predict the hardness of the Barbari bread (R 2 = 0.98) and specific volume of the Lavash bread (R 2 = 0.98). Overall, the results indicated that the regression models in the form of step-wise might be useful as a non-destructive technique for assessing quality of bread.

Restricted access

Abstract

Favipiravir (FVP), a pyrazine analog, has shown antiviral activity against a wide variety of viruses. It is considered to be worth further investigation as a potential candidate drug for COVID-19. It is not officially available in any pharmacopoeia. A rapid, simple, precise, accurate, and isocratic high performance liquid chromatography (HPLC) method has been developed for routine quality control of favipiravir in pharmaceutical formulations. Separation was carried out by C18 column. The mobile phase was a mixture of 50 mM potassium dihydrogen phosphate (pH 2.3) and acetonitrile (90:10, v/v) at a flow rate of 1 mL min−1. The ultraviolet (UV) detection and column temperature were 323 nm, and 30 °C, respectively. The run time was 15 min under these chromatographic conditions. Excellent linear relationship between peak area and favipiravir concentration in the range of 10–100 μg mL−1 has been observed (r 2, 0.9999). Developed method has been found to be sensitive (limits of detection and quantification were 1.20 μg mL−1 and 3.60 μg mL−1, respectively), precise (the interday and intraday relative standard deviation (RSD) values for peak area and retention time were less than 0.4 and 0.2%, respectively), accurate (recovery, 99.19–100.17%), specific and robust (% RSD were less than 1.00, for system suitability parameters). Proposed method has been successfully applied for quantification of favipiravir in pharmaceutical formulations.

Open access

Abstract

Citrus reticulata cv. Chachiensis, a traditional Chinese herb, has extensive medicinal and edible effects. 3′,4′,5,6,7,8-Hexamethoxyflavone (HM) and 5,6,7,8,4′-pentamethoxyflavone (PM) are main bioactive compounds in Chachiensis, which have been reported to possess various biological properties. In this study, supercritical CO2 extraction (SCE) and high-speed countercurrent chromatography (HSCCC) were utilized to prepare HM and PM from Chachiensis. The contents of target compounds were determined by a high-performance liquid chromatography method with diode-array detection (HPLC-DAD), which was validated using the following parameters: linearity, sensitivity, repeatability, stability, precision and accuracy. The SCE conditions were optimized using response surface methodology with central composite design. Obtained optimum conditions were temperature of 37.9 °C, pressure of 26.3 MPa, and modifier volume of 81.0 mL. Under above conditions, the recoveries of target compounds were 92.52 ± 0.83 and 96.36 ± 0.43%, respectively. The most appropriate solvent system for HSCCC was selected as n-hexane/ethyl acetate/methanol/water (1:0.8:1:1.2, v/v). The HSCCC fractions were detected by HPLC-DAD, liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (1H NMR and 13C NMR). The results indicated that this method was successfully applied to obtain HM and PM with high purities and high recoveries from Chachiensis.

Open access
Acta Chromatographica
Authors: Y.T. Kamal, Sayeed Ahmad, Nanjaian Mahadevan, Prawez Alam, Shahana Salam, Yahya I Asiri, Abdullatif Bin Muhsinah and Abdulrhman Alsayari

Abstract

A new High Performance Liquid Chromatography–Photodiode Array Detector (HPLC–PDA) method has been developed for the chromatographic separation and simultaneous quantitative determination of nine bioactive compounds, i.e. four phenolic (gallic acid, ellagic acid, chebulinic acid, and tannic acid), two flavanoids (rutin and quercetin), two anthraquinones (sennoside A and B) and one oxygenated hydrocarbon (vitamin C) in a well-known Unani polyherbal formulation namely Itrifal's. Separation was accomplished on a C18 LiChrospher 100 column (5 µm, 250 × 4.6 mm) with a gradient elution and recorded at 254 nm. The results demonstrated that the proposed method is reproducible, accurate, economic, and suitable for the quality control of traditional polyherbal Unani formulations containing complex compounds with different structures such as Itrifals.

Open access
Acta Chromatographica
Authors: Y.T. Kamal, Sayeed Ahmad, Nanjaian Mahadevan, Prawez Alam, Shahana Salam, Yahya I Asiri, Abdullatif Bin Muhsinah and Abdulrhman Alsayari

Abstract

A new High Performance Liquid Chromatography–Photodiode Array Detector (HPLC–PDA) method has been developed for the chromatographic separation and simultaneous quantitative determination of nine bioactive compounds, i.e. four phenolic (gallic acid, ellagic acid, chebulinic acid, and tannic acid), two flavanoids (rutin and quercetin), two anthraquinones (sennoside A and B) and one oxygenated hydrocarbon (vitamin C) in a well-known Unani polyherbal formulation namely Itrifal's. Separation was accomplished on a C18 LiChrospher 100 column (5 µm, 250 × 4.6 mm) with a gradient elution and recorded at 254 nm. The results demonstrated that the proposed method is reproducible, accurate, economic, and suitable for the quality control of traditional polyherbal Unani formulations containing complex compounds with different structures such as Itrifals.

Open access

Abstract

In this work, Gas chromatograph-Mass Spectrometry (GC-MS) combined with solid phase micro-extraction technology was used to analyze the difference of volatile organic compounds (VOCs) in rapeseed oil of different grades, and the relationship between changes of VOCs and refining process were also investigated in order to construct a non-linear model, which could realize rapid and accurate discrimination of different grade rapeseed oils. 124 rapeseed oil samples with different grades were collected and analyzed by GC-MS technology and 55 VOCs were identified and selected as variables to characterize the internal quality information of rapeseed oils. Then, principal component analysis (PCA) method was used to extract useful features and reduce data dimensionality, and finally a discriminant model was built using linear discriminant analysis (LDA) algorithm. The correct recognition rate of sample set was close to 94.59%. The results showed that the proposed method is promising in discriminating different grades of vegetable oils. Besides, it provides a theoretical basis for studying the relationship between VOCs composition and vegetable oil quality.

Open access

Abstract

The aim of the experiment is to establish a method for the determination of acrylamide in food by automatic accelerated solvent extraction-gas chromatography-mass spectrometry. D3-acrylamide was used as isotope internal standard, crushed samples were extracted and purified by automatic accelerated solvent, acrylamide was derivatized into 2,3-dibromopropanamide by potassium bromide and potassium bromate under acidic conditions, and then the derivative was extracted by ethyl acetate and detected by gas chromatography-mass spectrometry. The method had a good linear relationship in the concentration range of 10–2000 ng/mL, and the coefficient of determination (R2) was 0.9997. The detection limit of the method was 3 μg/kg. The quantification limit of the method was 10 μg/kg. The standard addition recovery of acrylamide was between 105 and 120%, and the relative standard deviation of the recovery of acrylamide was less than 3.0%. The experimental result showed that the method was simple, sensitive, efficient and accurate, and could be used for the determination of acrylamide in food.

Open access

Abstract

The aim of the experiment is to establish a method for the determination of acrylamide in food by automatic accelerated solvent extraction-gas chromatography-mass spectrometry. D3-acrylamide was used as isotope internal standard, crushed samples were extracted and purified by automatic accelerated solvent, acrylamide was derivatized into 2,3-dibromopropanamide by potassium bromide and potassium bromate under acidic conditions, and then the derivative was extracted by ethyl acetate and detected by gas chromatography-mass spectrometry. The method had a good linear relationship in the concentration range of 10–2000 ng/mL, and the coefficient of determination (R2) was 0.9997. The detection limit of the method was 3 μg/kg. The quantification limit of the method was 10 μg/kg. The standard addition recovery of acrylamide was between 105 and 120%, and the relative standard deviation of the recovery of acrylamide was less than 3.0%. The experimental result showed that the method was simple, sensitive, efficient and accurate, and could be used for the determination of acrylamide in food.

Open access
Acta Chromatographica
Authors: Stefano Dugheri, Giorgio Marrubini, Nicola Mucci, Giovanni Cappelli, Alessandro Bonari, Ilenia Pompilio, Lucia Trevisani and Giulio Arcangeli

Abstract

Sample pretreatment is one of the most crucial and error-prone steps of an analytical procedure; it consents to improve selectivity and sensitivity by sample clean-up and pre-concentration. Nowadays, the arousing interest in greener and sustainable analytical chemistry has increased the development of microextraction techniques as alternative sample preparation procedures. In this review, we aimed to show two different categorizations of the most used micro-solid-phase extraction (μSPE) techniques. In essence, the first one concerns the solid-phase extraction (SPE) sorbent selection and structure: normal-phase, reversed-phase, ion-exchange, mixed-mode, molecular imprinted polymer, and special techniques (e.g., doped cartridges for specific analytes). The second is a grouping of the commercially available μSPE products in categories and sub-categories. We present every device and technology into the classifications paying attention to their historical development and the actual state of the art. So, this study aims to provide the state-of-the-art of μSPE techniques, highlighting their advantages, disadvantages, and possible future developments in sample pretreatment.

Open access

Abstract

A sensitive RP-HPLC method is presented for the simultaneous quantification of Fluorometholone (FLM) and Tetrahydrozoline hydrochloride (THZ). The method has the advantages of being rapid, accurate, reproducible, ecologically acceptable and sensitive. The separation utilized C8 Xbridge® column and mobile phase mixture of Acetonitrile/phosphate buffer pH 3 ± 0.1 (70:30, v/v) with UV detection at 230 nm. Stepwise optimization and factors affecting separation are properly discussed. Different factors were optimized such as stationary phase, selection of organic solvent and its content, buffer pH and concentration, flow rate, elution type and detection wavelength. The studied drugs were efficiently separated in 3.4 min with high resolution. Also, two univariate spectrophotometric methods have been optimized for the quantification of the studied drugs. Method 1: dual wavelength for THZ and iso-absorptive point for FLM, Method 2: ratio difference (RD) for THZ and first derivative FLM utilizing methanol as a solvent. These methods are accurate, precise with minimal data manipulation. Greenness of the methods was estimated using eco-scale tool where the presented methods were found to be excellent green with eco-score of 83 for HPLC and 80 for spectrophotometry. The methods are validated in conformance with ICH guidelines, with acceptable accuracy, precision, and selectivity. The suggested methods can be employed for the economic analysis of THZ and FLM in their pure form and binary ophthalmic formulation, that can be employed by quality control laboratories.

Open access

Abstract

A method for simultaneous determination of trace of four organophosphorus pesticides residues in animal liver samples has been developed and validated. This method is based on the preliminary sample preparation using extraction of target compound with a mixture of toluene-cyclohexane by means of up-to-date accelerated solvent extraction (ASE), liquid-liquid partitioning with acetonitrile and hexane, additional clean up step using QuEChERS method. Further the obtained analytes are determined by gas chromatography with ion-trap detector. The validation of the method is performed in accordance with the recommendations in Document SANTE/11945/2015 and it meets the acceptability criteria for precision, mean recovery and limits of quantification. The samples were investigated by analysing blank liver samples and samples spiked with the target analytes chlorpyrifos-methyl, parathion and pirimiphos-methyl at levels of 25, 50, and 75 ng/g and with diazinon at levels of 15, 30, and 45 ng/g. The recovery for all compounds were in the range from 73 to 104% which perfectly fit with requirements of documents and European legislations. The repeatability and within-laboratory reproducibility also reveal acceptable in documents coefficient of variation and uncertainty less than 20 and 18%, respectively. The limits of quantification were less than 3 ng/g for all compounds and allowed determination of residues below the maximum residue levels (MRLs) set in Regulation (EC) Nº 396/2005.

Open access

Abstract

A simple and sensitive high-performance liquid chromatography-ultraviolet (HPLC-UV) method was developed by exploiting the benefits of phenyl-hexyl column for the simultaneous determination of mono- and di-caffeoylquinic acids in Gynura procumbens plant samples. An optimal chromatographic separation was achieved by using a mobile phase of acetonitrile: 0.25% acetic acid in water (12.5:78.5, v/v) and detection at 330 nm. The limits of detection (LOD) and quantification (LOQ) for the six caffeoylquinic acid standards were in the range of 0.078–0.653 and 0.259–1.795 μg/mL, respectively. The accuracies of the developed method were in the range of 96.84–103.08%, while the corresponding precisions were between 0 and 2.94% for both within-day and between-day analyses, indicating that the method is repeatable and reliable. The mean recoveries were between 87.08 and 117.83%. The method was successfully applied for quantification of caffeoylquinic acids in G. procumbens plant samples. This is the first study on di-caffeoylquinic acids quantification in G. procumbens. Leaves samples contained higher amount of the caffeoylquinic acids compared to stem samples. Of the compounds, 3,5-dicaffeoylquinic acid was found to be the major compound in almost all G. procumbens samples. The method has advantages such as sensitive ultraviolet (UV) detection, short run time with simple isocratic elution system compared to other methods which involved the use of costly instruments, laborious procedures with long run time and complex gradient system. This method can be further extended for routine quality control and analysis of plants or herbal products containing the caffeoylquinic acids.

Open access
Acta Chromatographica
Authors: Muhammad Hanif, Shahid Shah, Nasir Rasool, Ghulam Abbas, Malik Saadullah, Sajid Mehmood Khan, Muhammad Masood Ahmed, Nazar Abbas, Mehran Ashfaq and Omeira Iqbal

Abstract

The high performance liquid chromatographic (HPLC) method was developed for the combined estimation of sodium alginate and pectin in raft forming pharmaceuticals on C18 column ZORBAX ODS (1.5 cm × 4.6 mm, 5 μm) with UV detection at 378 nm. The assay condition comprised of phosphate buffer pH 7.4 and methanol 60:40% v/v at a flow rate of 1.25 mL/min. The separation of sodium alginate and pectin with good resolution and a retention time less than 8 min was attained. The method was linear over a range of 200–800 μg/mL of sodium alginate and pectin. The regression values obtained from linearity curve of sodium alginate and pectin were 0.9993 and 0.9991, respectively. The retention time of sodium alginate and pectin was 3.931 and 7.470 min, respectively. The percent recovery of sodium alginate and pectin ranged from 94.2–98.5% and 92.1–98.4% respectively. The limit of detection (LOD) and limit of quantification (LOQ) of sodium alginate were found to be 2.443 and 3.129 μg/mL and the LOD and LOQ of pectin were 3.126 and 3.785 μg/mL, respectively. The resolution of sodium alginate and pectin was found in the range of 1.03–1.89 and 1.10–1.91, respectively. This method has been successfully applied to analyze the concentrations of sodium alginate and pectin in raft forming drug delivery systems.

Open access

Abstract

Toddalia asiatica (Linn) Lam (T. asiatica) as a traditional Miao medicine was investigated to find rational alternative medicinal parts for T. asiatica root bark and its antitumor chemical constituents by quantitative pharmacognostic microscopy, high performance liquid chromatography (HPLC) fingerprint and multivariate statistical analysis. A bivariate correlation analysis method based on microscopic characteristics and content of chemical constituents was established for the first time, there were some regular discoveries between powder microscopic characteristics and common chromatographic peaks of T. asiatica through quantitative pharmacognostic microscopy, cork cells, calcium oxalate square crystal, brown clump, starch granule and phloem fiber, as powder microscopic characteristics may be placed where the main chemical constitutes were enriched. Scores plot of principal component analysis (PCA) and dendrogram of hierarchical clustering analysis (HCA) showed that 18 T. asiatica samples were distinguished correctly, clustered clearly into two main groups as follows: S01∼S03 (root bark) and S07∼S09 (stem bark) in cluster 1, S04∼S06 and S10∼S18 in cluster 2. Nineteen common peaks were obtained in HPLC fingerprint of T. asiatica, loadings plot of PCA indicated seven compounds played important roles in different part of samples (P10 > P08 > P07 > P14 > P16 > P17 > P19), peaks 04, 06, 07, 08, 10 were identified as hesperidin, 4-methoxycinnamic acid, toddalolactone, isopimpinlline and pimpinellin. MTT assay was used to determine the inhibitory activity of different medicinal parts of T. asiatica on human breast cancer MCF-7 cells, all parts of T. asiatica had different inhibitory effects on MCF-7 cell lines, root and stem barks of T. asiatica showed the best inhibitory activity. The relationship between chemical constituents and the inhibitions on MCF-7 cell had been established, significant antitumor constituents of T. asiatica were identified by correlation analysis, the order of the antitumor effect of the main compounds was P07 (toddalolactone) > P16 > P06 (4-methoxycinnamic acid), P11 > P18 > P10 (pimpinellin) > P08 (isopimpinellin) > P01 > P19 > P14 > P04 (hesperidin) > P17, which were antitumor chemical constituents of T. asiatica root bark. T. asiatica stem bark was the most rational alternative medicinal part for T. asiatica root bark.

Open access

Abstract

In this research, cannabis varieties represent 23 USA States were assayed by GC-FID to generate their complex chemical profiles informative for plants clustering. Results showed that 45 cannabinoids and terpenoids were quantified in all plant samples, where 8 cannabinoids and 18 terpenoids were identified. Among organics, Δ9-THC, CBN (cannabinoids) and Fenchol (terpenoid) not only showed the highest levels overall contents, but also were the most important compounds for cannabis clustering. Among States, Washington, Oregon, California and Hawaii have the highest cannabis content. GC-FID data were subjected to PCA and HCA to find (1) the variations among cannabis chemical profiles as a result of growing environment, (2) to reveal the compounds that were responsible for grouping cultivars between clusters and (3) finally, to facilitate the future profile prediction and States clustering of unknown cannabis based on the chemical profile. The 23 cannabis USA States were grouped into three clusters based on only Δ9-THC, CBN, C1 and Fenchol content. Cannabis classification based on GC-profile will meet the practical needs of cannabis applications in clinical research, industrial production, patients' self-production, and contribute to the standardization of commercially-available cannabis cultivars in USA.

Open access

Abstract

In this research, cannabis varieties represent 23 USA States were assayed by GC-FID to generate their complex chemical profiles informative for plants clustering. Results showed that 45 cannabinoids and terpenoids were quantified in all plant samples, where 8 cannabinoids and 18 terpenoids were identified. Among organics, Δ9-THC, CBN (cannabinoids) and Fenchol (terpenoid) not only showed the highest levels overall contents, but also were the most important compounds for cannabis clustering. Among States, Washington, Oregon, California and Hawaii have the highest cannabis content. GC-FID data were subjected to PCA and HCA to find (1) the variations among cannabis chemical profiles as a result of growing environment, (2) to reveal the compounds that were responsible for grouping cultivars between clusters and (3) finally, to facilitate the future profile prediction and States clustering of unknown cannabis based on the chemical profile. The 23 cannabis USA States were grouped into three clusters based on only Δ9-THC, CBN, C1 and Fenchol content. Cannabis classification based on GC-profile will meet the practical needs of cannabis applications in clinical research, industrial production, patients' self-production, and contribute to the standardization of commercially-available cannabis cultivars in USA.

Open access

Abstract

Fifty four domestically produced cannabis samples obtained from different USA states were quantitatively assayed by GC–FID to detect 22 active components: 15 terpenoids and 7 cannabinoids. The profiles of the selected compounds were used as inputs for samples grouping to their geographical origins and for building a geographical prediction model using Linear Discriminant Analysis. The proposed sample extraction and chromatographic separation was satisfactory to select 22 active ingredients with a wide analytical range between 5.0 and 1,000 µg/mL. Analysis of GC-profiles by Principle Component Analysis retained three significant variables for grouping job (Δ9-THC, CBN, and CBC) and the modest discrimination of samples based on their geographical origin was reported. PCA was able to separate many samples of Oregon and Vermont while a mixed classification was observed for the rest of samples. By using LDA as a supervised classification method, excellent separation of cannabis samples was attained leading to a classification of new samples not being included in the model. Using two principal components and LDA with GC–FID profiles correctly predict the geographical of 100% Washington cannabis, 86% of both Oregon and Vermont samples, and finally, 71% of Ohio samples.

Open access

Abstract

Sodium polystyrene sulfonate (SPS) powder is in use for over 50 years for the treatment of hyperkalemia. SPS powder is official in United States Pharmacopoeia, British Pharmacopoeia and European Pharmacopoeia. However, till date, no study has been published on the assessment of organic impurities for this drug. The organic impurities in bulk drug and finished product are associated with their safety, efficacy and stability. A simple, rapid, specific, precise and an accurate HPLC method has been developed for the estimation of toxic organic impurities like styrene, naphthalene, divinyl benzene (DVB) and ethylvinyl benzene (EVB) from SPS bulk drug and finished product. The developed method was validated for specificity, accuracy, precision, linearity, limit of detection (LOD), limit of quantitation (LOQ), solution stability, ruggedness and robustness. The influence of acid, alkali, oxidative stress, photolytic stress, thermal stress and humidity stress conditions on SPS bulk powder and finished product has been studied and reported. The proposed method can be successfully employed for the impurity testing of commercial batches of the bulk drug and finished products of both sodium salt and calcium salt of polystyrene sulfonate.

Open access

Abstract

Mono- and bis-pyridinium quaternary aldoximes (K-oximes) have long been employed as cholinesterase reactivator components of antidotes against lethal cholinesterase-inhibiting organophosphorous chemicals. Their positive charge poses difficulties in their chromatographic analysis, resulting in the publication of different approaches for each K-oxime. A multiplexed method is presented for the rapid quantitation of 10 K-oximes in blood with its utility demonstrated in vivo. Liquid chromatography with absorbance detection was employed. Reversed-phase separation was achieved on a highly nonpolar stationary phase. Method validation was based on the respective guideline of the European Medicines Agency. Times to peak concentrations and 120-min areas under the time–concentration curves were determined in rats following intraperitoneal administration. Adequate retention and separation of K-oximes with acceptable peak shapes in short isocratic runs was achieved by adjusting ionic strength, organic content and the concentration of the ion-pairing agent of the mobile phase. Chromatographic properties were governed by optimizing the concentration of dissolved ions. Accurate adjustment of the organic content was indispensable for avoiding peak drifting and splitting. Dose-adjusted exposure to K-347 and K-868 was exceptionally low, while exposure to K-48 was the highest. The method is suitable for screening systemic exposure to various K-oximes and can be extended.

Open access

Abstract

This study presents the optimization and validation of methods for the analysis of retinol, thiamine, niacin, pyridoxine, folic acid, cyanocobalamin, zinc, and iron in fortified kernels (coated and extruded) and in fortified rice. The analyses were performed by HPLC-UV/FLD/MS and ICP-OES. The optimized methods showed good resolution of the analyte peaks, excellent recovery (87–108%), reproducibility with relative standard deviation (SD) of analyte content between 1.8 and 11% and high correlation coefficient of the calibration curves (R2 > 0.997). Limit of detection was from 2.8 E-4 mg/kg for pyridoxine to 1.26 mg/kg for zinc and limit of quantification was from 9.2 E-4 mg/kg for pyridoxine to 4.21 mg/kg for zinc. Thereby the optimized methods demonstrated reliability and sensitivity in the detection and quantification of these micronutrients and that they are suitable for routine analysis of fortified kernels (coated and extruded) and fortified rice.

Open access

Abstract

This study describes the development and validation of a simple, specific, accurate, and precise method for quantitative determination of Esomeprazole in human serum using Pantoprazole as internal standard (IS). After the addition of internal standard, Esomeprazole from serum samples was extracted simply by protein precipitation method followed by centrifugation and the supernatants were directly injected into the high performance liquid chromatography (HPLC). The chromatographic separation of the compounds was obtained on Hitachi Lachrom C8 column (5 µm, 250 × 4.6 mm) with a mobile phase consisting of 5 mM potassium dihydrogen phosphate pH 7.4 and acetonitrile in a ratio of 70:30 with UV detection at 302 nm with a flow rate of 1 mL/min. The method was sensitive and specific, and validated over a concentration range of 0.06–6.0 µg/mL. The limit of detection (LOD) and lower limit of quantification (LOQ) was 0.03 µg/mL and 0.06 µg/mL, respectively. The precision and accuracy expressed as relative standard deviation were less than 15%. The average recovery of Esomeprazole from serum was 97.08%.

Open access

Abstract

A rapid and sensitive High-Performance Liquid Chromatography-tandem Mass Spectrometry (HPLC/MS/MS) method for determining apremilast in beagle dog plasma and urine samples was developed and validated using clopidogrel as the internal standard (IS). Apremilast was extracted from the plasma and urine samples by liquid–liquid extraction using methyl tert-butyl ether. Chromatographic separation was performed using a C8 column with gradient elution and a mobile phase containing methanol and 0.1% formic acid. Quantification was achieved in multiple reaction monitoring (MRM) mode with a transition of m/z 461.3→178.2 for apremilast and m/z 322.2→184.1 for clopidogrel (IS). This method was validated regarding its specificity, linearity, precision, accuracy, and stability. The lower limit of quantification (LLOQ) for this method was 5 ng/mL, and the calibration curve was linear over 5–1,000 ng/mL. The intra- and inter-run coefficients of variance (CV) of aprelimast in plasma samples were less than 12.92% and 10.64%, respectively, while in urine samples, the CV were less than 11.84% and 10.20%, respectively. The samples were stable under the tested conditions. This method was successfully applied to a pharmacokinetic study in beagle dogs following oral administration of 10 mg of apremilast.

Open access

Abstract

Calycanthine is an important class of alkaloids extracted and isolated from the roots, leaves, flowers and fruits of Chimonanthus praecox. In this work, the UPLC-MS/MS method was used for determination of calycanthine in rat plasma, and the pharmacokinetics in rats were investigated. Midazolam was used as an internal standard (IS), and methanol precipitation method was used to pretreatment the rat plasma samples. Chromatographic separation was achieved on a UPLC BEH C18 (50 × 2.1 mm, 1.7 μm) column with the mobile phase of methanol- 0.1% formic acid aqueous solution with gradient elution. Multiple reaction monitoring (MRM) mode with positive ionization was applied for quantitative analysis, m/z 347.3 → 246.7 and 326.2 → 291.4 for calycanthine and IS, respectively. The results indicated that within the range of 1–200 ng/mL, linearity of calycanthine in rat plasma was good (r > 0.995), and the lower limit of quantification (LLOQ) was 1 ng/mL. Accuracy range was between 90.6 and 109.4%, precision (RSD) of calycanthine was less than 14%. The matrix effect was between 97.9% and 105.4%, the recovery was better than 85.6%. The developed UPLC-MS/MS method was successfully applied in the pharmacokinetics of calycanthine in rats after oral and intravenous administration. The absolute bioavailability of the calycanthine was 37.5% in rats.

Open access

Abstract

Calycanthine is an important class of alkaloids extracted and isolated from the roots, leaves, flowers and fruits of Chimonanthus praecox. In this work, the UPLC-MS/MS method was used for determination of calycanthine in rat plasma, and the pharmacokinetics in rats were investigated. Midazolam was used as an internal standard (IS), and methanol precipitation method was used to pretreatment the rat plasma samples. Chromatographic separation was achieved on a UPLC BEH C18 (50 × 2.1 mm, 1.7 μm) column with the mobile phase of methanol- 0.1% formic acid aqueous solution with gradient elution. Multiple reaction monitoring (MRM) mode with positive ionization was applied for quantitative analysis, m/z 347.3 → 246.7 and 326.2 → 291.4 for calycanthine and IS, respectively. The results indicated that within the range of 1–200 ng/mL, linearity of calycanthine in rat plasma was good (r > 0.995), and the lower limit of quantification (LLOQ) was 1 ng/mL. Accuracy range was between 90.6 and 109.4%, precision (RSD) of calycanthine was less than 14%. The matrix effect was between 97.9% and 105.4%, the recovery was better than 85.6%. The developed UPLC-MS/MS method was successfully applied in the pharmacokinetics of calycanthine in rats after oral and intravenous administration. The absolute bioavailability of the calycanthine was 37.5% in rats.

Open access

Abstract

Twelve Sprague-Dawley rats were randomly divided into two groups: Citrus suavissima Hort. ex Tanaka group and control group (n = 6). The rats in Citrus suavissima Hort. ex Tanaka group were given Citrus suavissima Hort. ex Tanaka juices (1 mL/100 g) by oral administration each day, continued for 14 days; the rats in control group were given Stroke-physiological saline solution (1 mL/100 g) by oral administration each day, continued for 14 days. The rats of these two groups were given a single oral administration of erlotinib (20 mg/kg) on the 15th day. After blood sampling at different time points and processing, the concentrations of erlotinib in rat plasma were determined by the established ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. Chromatographic separation was achieved using a UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) with erlotinib-d6 as an internal standard (IS). The initial mobile phase consisted of acetonitrile and water (containing 0.1% formic acid) with gradient elution. Multiple reaction monitoring (MRM) modes were utilized to conduct quantitative analysis. The sensitive, rapid and selective UPLC-MS/MS method was successfully applied to analyse the effect of Citrus suavissima Hort. ex Tanaka on pharmacokinetics of erlotinib in rat plasma. There were no significant differences in AUC(0−t), t 1/2, T max, CL, C max between the two groups (P > 0.05). While MRT(0−t) was decreased (P < 0.05) in Citrus suavissima Hort. ex Tanaka group, compared to the control group. It showed that Citrus suavissima Hort. ex Tanaka could not affect the metabolism of erlotinib.

Open access
Acta Chromatographica
Authors: Jinzhao Yang, Huamin Liu, Yuan Cai, Yazhen Wu, Xiaoxin Xu, Xianqin Wang and Chongliang Lin

Abstract

Twelve Sprague-Dawley rats were randomly divided into two groups: Citrus suavissima Hort. ex Tanaka group and control group (n = 6). The rats in Citrus suavissima Hort. ex Tanaka group were given Citrus suavissima Hort. ex Tanaka juices (1 mL/100 g) by oral administration each day, continued for 14 days; the rats in control group were given Stroke-physiological saline solution (1 mL/100 g) by oral administration each day, continued for 14 days. The rats of these two groups were given a single oral administration of erlotinib (20 mg/kg) on the 15th day. After blood sampling at different time points and processing, the concentrations of erlotinib in rat plasma were determined by the established ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. Chromatographic separation was achieved using a UPLC BEH C18 column (2.1 mm × 50 mm, 1.7 μm) with erlotinib-d6 as an internal standard (IS). The initial mobile phase consisted of acetonitrile and water (containing 0.1% formic acid) with gradient elution. Multiple reaction monitoring (MRM) modes were utilized to conduct quantitative analysis. The sensitive, rapid and selective UPLC-MS/MS method was successfully applied to analyse the effect of Citrus suavissima Hort. ex Tanaka on pharmacokinetics of erlotinib in rat plasma. There were no significant differences in AUC(0−t), t 1/2, T max, CL, C max between the two groups (P > 0.05). While MRT(0−t) was decreased (P < 0.05) in Citrus suavissima Hort. ex Tanaka group, compared to the control group. It showed that Citrus suavissima Hort. ex Tanaka could not affect the metabolism of erlotinib.

Open access

Abstract

A simple, inexpensive and sensitive method was developed for the simultaneous determination of three pesticide residues (carbendazim, thiophanate-methyl, and imidacloprid) in fruit and vegetable samples using high performance liquid chromatography (HPLC) based on a combined pretreatment of ultrasound-assisted deep eutectic solvent extraction (UA-DES-E) and liquid-liquid extraction (LLE). In this study, various types of deep eutectic solvents (DESs) were synthesized and the extraction efficiency was compared as extraction solvents. Results showed that glycerol-proline = 9:4 (GP-5) obtained the highest extraction efficiency among different types of DESs. Experiment conditions, including DES volume, extraction time and pH, were systematically optimized using single-factor experiment. Under the optimum conditions, the limits of detection (LODs) and quantification (LOQs) were in the ranges of 0.05–0.2 μg·mL−1 and 0.1–0.5 μg·mL−1, respectively. The relative recoveries of the three pesticides in the fruit and vegetable samples ranged from 85.7 to 113.0% at two spiked levels. Meanwhile, the method achieved excellent linearity with determination coefficients (r) greater than 0.999. Furthermore, the method was successfully applied to the analysis of the pesticides in real fruit and vegetable samples (apple, tomato, and grape).

Open access