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Abstract

In this study, a UPLC-MS/MS method was developed for determination of pancratistatin in the mouse blood, and the pharmacokinetics of pancratistatin in mice after intravenous (5 mg kg−1) and intragastric (15 mg kg−1) administration was studied. HSS T3 column was used for separation with mobile phases of acetonitrile and 0.1% formic acid using gradient elution procedure. The blood sample was treated by protein precipitant with acetonitrile, midazolam was used as internal standard (IS). Multiple reaction monitoring mode (MRM) was used for quantitative analysis, m/z 326.2→83.8 for pancratistatin and m/z 326.2→291.4 for IS in electrospray (ESI) positive interface. It showed a good linear in the range of 10–4,000 ng mL−1 (r > 0.998); the intra-day and inter-day precision was <15%, and the accuracy was 93%–105%. The recovery was better than 82%, and the matrix effect was 94%–105%. The developed UPLC-MS/MS method was fast, selective, and suitable for the pharmacokinetics of pancratistatin in mice.

Open access

Abstract

The rapid technological development that is still taking place today, with increasingly interconnected IT tools, is introducing dramatic changes. The development of computer programs is rapidly transforming traditional processes and the systems that support them. It is therefore natural that the fourth industrial revolution (Industry 4.0) and its impact on Hungarian companies is one of the key topics of our time. We conducted an exploratory quantitative survey, asking 140 managers of Hungarian small, medium and large enterprises about their current situation in the context of Industry 4.0. We sought to find out to what extent the specific R&D and innovation potential of Industry 4.0 is accepted, and whether it has already been introduced in the companies. On a qualitative side, 2 case studies and 3 interviews were conducted, in which structured interviews were used to further explore the issue. We aimed to find out where SMEs stood in terms of digital preparedness and what advantages, possible disadvantages, and goals they managed to identify. Our research showed that an increasing number of companies have already decided to take the first steps towards industrial digitalisation, which will completely transform their internal processes.

Open access

Abstract

A rapid and simple method for the determination of stearic acid and 12-hydroxystearic acid in PEG-60 hydrogenated castor oil by high performance liquid chromatography with evaporative light scattering detection was established. The oil sample was first pretreated by alkaline hydrolysis. The analysis was performed on a Zhongpu Develop XD-C18 column (250 mm × 4.6 mm, 5 µm) with gradient elution of methanol and 1% acetic acid aqueous solution at a flow rate of 1.2 mL·min−1 and a column temperature of 40 °C. The drift tube temperature of the evaporative light scattering detection system was set at 40 °C, and the pressure of carrier gas (N2) was 337 kPa. The regression equation revealed a good linear relation (r = 0.9993–0.9995) during the test ranges (119.1–1190.7 μg·mL−1 for 12-hydroxystearic acid, 10.7–107.4 μg·mL−1 for stearic acid). The detection limits of 12-hydroxystearic acid and stearic acid were 1.1 and 2.5 μg·mL−1, the limits of quantitation were 3.2 and 7.4 μg·mL−1, respectively. And the mean recoveries were 101.5 and 101.0%, the corresponding relative standard deviations (RSDs) were 2.1 and 2.8%, respectively. The RSDs corresponding to repeatability (n = 6) were both less than 1.7% in terms of precision. As to the stability, the test results remained stable after 8 h at room temperature (RSDs were both less than 2.6%). The developed method showed high sensitivity, recovery, repeatability and stability, which indicated that the method could be applied as a quality evaluation method for the determination of stearic acid and 12-hydroxyoctadecanoic acid in PEG-60 hydrogenated castor oil.

Open access

Abstract

Indapamide (Indp) and certain other diuretics have been abused in sports, therefore, having sensitive methods for its detection and assay in biological fluids (whole blood, plasma, serum, and urine) is of significant importance. The racemic mixture of Indp is being used as an active pharmaceutical ingredient among other commonly prescribed diuretics. The regulatory authorities and pharmaceutical industries demand analytical methods for successful enantioseparation of such molecules. The paper presents a critical overview of the scientific issues of the application of contemporary techniques involving various chromatographic approaches (with liquid or supercritical fluid as mobile phases) and capillary electrophoresis and method development, for drug screening, assay, bioequivalence studies and enantioseparation of indapamide with their results. It also covers the historical developments that led to significant breakthroughs in research and concise evaluations of research in the area.

Different types of chromatographic methods (HPLC, CEC, SFC etc) discussed herein provide an insight and a choice to select a method to (i) screen Indp for drug abuse, (ii) separate, isolate and quantify the enantiomers of Indp and (iii) investigate their pharmacokinetics as markedly different species and not as a total drug. The article evaluates the field's status with a broad base and practical oriented approach so that the underlying principles are easily understood to help chemists and non-specialists gain useful insights into the field outside their specialization and provide experts with summaries of key developments. To the best of authors' knowledge there has been no attempt to review such methods for analysis of Indp and this is the first report of its kind.

Open access

Rambutan (Nephelium lappaceum) production is growing worldwide so the treatment and utilization of Rambutan by-products has become a concern of manufacturers. The objective of this study was to evaluate the potential application of rhizobacteria to decompose Rambutan peel for organic fertilizer production. After the rhizospheric soil samples were selectively proliferated and preadded on agar medium containing only Rambutan peel, the rhizobacterial colony isolates were screened based on their ability to grow on this agar medium and then to degrade cellulose in Rambutan peel. The LD7.3 isolate from the Rambutan rhizosphere showed the highest efficiency in degrading Rambutan peel with 5.6% degraded cellulose content and was identified by the MALDI-TOF technique as belonging to Klebsiella. Klebsiella sp. LD7.3 grew well and maintained the same degrading activity after three times of subculturing in liquid medium. Notably, the supplementation of grinded Rambutan fruit peel to the liquid medium had a positive effect on the growth and the degrading activity of Klebsiella sp. LD7.3. This was the primary report on the application of rhizobacteria to degrade Rambutan peel and the results showed that this was a potential approach to reuse this waste source.

Restricted access

The experiment was conducted within a framework of a two-factor long-term trial at the Research Institute for Fisheries, Aquaculture and Irrigation, in Szarvas, Hungary. This was a special field experiment, in which lysimeters have been installed in the middle of 32 m2 field plots. The main factor was the water supply with 4 levels: i1: non-irrigated control; i2: irrigated with one third of the optimal water supply; i3: irrigated with two thirds of the optimal water supply; i4: optimum irrigated plot, according to the requirement of sweet corn test plant. The amount of released irrigation water was 0, 54, 106 and 158 mm per year on average over 5 years. Within every water supply treatment there were 4 nutrient supply rates (N): N1, N2, N3, N4 = 100, 200, 300 and 400 kg ha−1 NPK fertiliser substance in ratio 2:1:1. The number of replications was 4, and the experiment was arranged in split-plot design. In the studied years, the amount of precipitation varied between 92 and 264 mm from sowing to harvesting.

The effect of fertiliser was less in the non-irrigated treatments compared to that of the irrigated ones, and the yield was increased only up to 200 kg ha−1 NPK treatment level. The NPK dose of 300 kg ha−1 proved to be optimal in the irrigated treatments in which the utilization of fertilizer doses increased parallel to the improving water supply. In addition, the ratio of first class products (cobs longer than 20 cm) increased to a greater extent than the yield as a result of irrigation and fertilization. Water requirement of sweet corn proved to be between 400–450 mm resulting in an average yield of 20–24 t ha−1, of which 18–20 t ha−1 came from marketable cobs. The amount of evapotranspiration fluctuated between 270–440 mm during the five years, depending on the quantity of water supply, but it changed to a lesser extent than the amount of the yield. Increasing the fertilizer dose practically did not affect ET in non-irrigated plants, but increased it by 20–30 mm in irrigated ones. The change was not significant.

The productivity of ET was only 30–45 kg ha−1 mm−1 in the non-irrigated treatment, while it was 50–55 kg ha−1 mm−1 in the irrigated treatments, with higher values at the higher fertiliser rates. The productivity of irrigation water exceeded far over the productivity of ET at adequate nutrient supply. The yield increase per 1 mm of irrigation water was on average 60 kg ha−1 mm−1, which was considerably higher than the productivity of ET of non-irrigated plants (39 kg ha−1 mm−1). There was a positive correlation between the yield and ET, and a negative correlation between the yield and specific water consumption. Irrigation and fertilization increased the average yield to a greater extent than evapotranspiration, so as the average yield increased, the ET per unit of yield decreased, i.e. the productivity of evapotranspirated water increased.

Open access

Abstract

Pregabalin is a gabapentinoid approved for the treatment of general anxiety disorder, neuropathic pain and as adjunctive therapy for focal seizures in patients with epilepsy. In addition, there are a number of conditions for which pregabalin is prescribed off-label. Along with the widespread use there are a significant number of reports describing the misuse of pregabalin over the last decade. Over time, it became clear that pregabalin should become part of routine testing in toxicology laboratories. The aim of this paper was to present validation of a LC-MS/MS method for the quantification of pregabalin in plasma of acutely poisoned patients. Simple sample preparation step and rapid chromatographic separation shortened the overall analysis time, which was the goal of method development. The presence of pregabalin was confirmed with three ion transitions, ensuring high selectivity of the validated method. The statistical data obtained showed good precision and accuracy over a wide concentration range. No endogenous or other interference was detected, and there was no matrix effect influence with this method. The LC-MS/MS method was applied to quantify pregabalin in plasma samples of patients admitted to the emergency department due to a possible acute pregabalin overdose. Different concentrations were found, and we report, to the best of our knowledge, the highest plasma concentration of pregabalin in the plasma of a patient with acute poisoning. In conclusion, we developed a fast and simple LC-MS/MS method for reliable determination of pregabalin and demonstrated the developed method was suitable for routine use in clinical toxicology setting.

Open access

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are persistent organic pollutants (POPs) that are widely distributed in the environment and cause significant environmental damage. Furthermore, they endanger human health by polluting food from the natural environment and food processing. Therefore, it is necessary to accurately detect PAHs in various sample matrices, which requires precise, practical, and rapid detection methods. The purpose of this research is to develop a high sensitivity analysis method by analyzing the optimum excitation and emission wavelengths of EPA's 15 priority polyaromatic hydrocarbons in the UHPLC fluorescence detector (Acenaphthene, Anthracene, Benzo[a]anthracene, Benzo[b]fluoranthene, Benzo[k]fluoranthene, Benzo[ghi]perylene, Benzo[a]pyrene, Chrysene, Dibenzo[a,h]anthracene, Fluoranthene, Fluorene, Indeno[1,2,3-cd]pyrene, Naphthalene, Phenanthrene, and Pyrene). An average of 17–25 analyses were performed for each polyaromatic hydrocarbon, and optimized excitation and emission wavelengths were obtained. LOD levels between 2 and 90 ppt were obtained with the method created in this direction. It is worth mentioning that the limits achieved for some PAH parameters are lower than those reported in the literature after pre-concentration steps.

Open access

Abstract

The two chemical components Escitalopram (ESC) and Etizolam (ETZ) are beneficial for the health of individuals because it helps to treat anxiety. The study mainly illustrated that a green approach is essential in the medical sector with the help of “Green Analytical quality by design”. According to AQbD, the techniques of HPTLC have become eco-friendly, and decided to use “ESC” and “ETZ”. Hence, ethanol and phosphate buffer pH 3.5 adjusted with 1% “orthophosphoric acid”. After the retardation factor, the product ESC was found at 0.34 min and ETZ was found at 0.53 min. The linearity of ETZ the range varies from 300 to 1800 μg mL−1 and for ESC it varies from 100 to 600 μg mL−1. The validation parameter of R 2 Values ranged from 0.9997 to 0.9994 for both ESC and ETZ. The study also demonstrated that different other methods were also useful for the medical sector to make it more convenient and eco-friendly. Some of those approaches are “GAPI”, “AGMS”, “NEMI”, and “AGREE”. The outcome of the study helped to find that the technique “HPTLC” is a green analytic design that helps to maintain the stability of the medicine and it was also approved as a quality design and also a novel approach in the pharmaceutical sector.

Open access