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Chemistry and Chemical Engineering

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Abstract

An ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the determination of nobiletin and tangeretin in rat plasma, and the plasma was processed by a simple liquid-liquid extraction method with ethyl acetate. The chromatographic column was UPLC HSS T3 (50 × 2.1 mm, 1.7 μm), the mobile phase was acetonitrile-water (containing 0.1% formic acid). Multiple reaction monitoring mode (MRM) was used for quantitative analysis, nobiletin m/z 403.29 → 373.14 (cone voltage 22v, collision voltage 28v), tangeretin m/z 373.28 → 343.17 (cone voltage 20v, collision voltage 28V), tangeretin m/z 373.28 → 343.17 (cone voltage 20V, collision voltage 28V) and internal standard vitexin m/z 433.14 → 313.03 (cone voltage 32v, collision voltage 26v). The pharmacokinetics of nobiletin and tangeretin were evaluated in rats. The established UPLC-MS/MS method in the range of 2–2,000 ng mL−1 was successfully applied to the pharmacokinetics, and the calculated bioavailability of nobiletin and tangeretin was 63.9 and 46.1%, respectively.

Open access

Abstract

Based on chromatographic fingerprinting combined with quantitative analysis on characteristic chemical constituents as well as hierarchical cluster analysis, an easy and sensitive approach utilizing high performance liquid chromatography (HPLC) was developed for the identification and quality evaluation of Rutongshu oral liquid (ROL). What is more, nontargeted metabolomic analysis was conducted to gain a global view in terms of its chemical profile. In this study, 16 peaks from different batches (S1–S10) of ROL samples produced by Taihe Hospital of Chinese Medicine were selected as common peaks for the evaluation of their similarity whose values of all tested 10 batches exceeded 0.90 when compared with the control fingerprints. Meanwhile, simultaneous quantification of five markers in the oral solution, including albiflorin, paeoniflorin, chlorogenic acid, quercetin and ferulic acid was performed, and standard curves established for respective reference substances showed good regression in the linear range (r 2 > 0.999) with recoveries in the range of 98.96–102.35%. The ultra-high performance liquid chromatography (UHPLC) combined with Orbitrap Exploris 120 mass spectrometer resulted in 88 identified compounds. The results of validation showed that the established method was reproducible, precise and stable. This study offers an effective, dependable and useful approach for the systematic evaluation of the hospital formulation ROL.

Open access

Abstract

Hydrochlorothiazide has been utilized clinically for the past half-century, which is popularly known as a “water pill” as it produces increased urine output. The advancement of bioanalytical methods brought a dynamic field with exciting opportunities for future research. The current review emphasis the bioanalytical methods employed for the quantitative estimation of Hydrochlorothiazide as monotherapy and its popularly used combinational medications available from 1956 to till date. A fixed dose of 25 mg of hydrochlorothiazide with 43 combinational medications is currently available in the market and these combinations are widely employed in the treatment of hypertensive people; those whose blood pressure does not respond effectively to monotherapy of hydrochlorothiazide and also for the treatment of edema (excess fluid in the body) caused by illness such as heart failure, liver problems, and renal disease. It has been convincingly demonstrated that the combination of any two antihypertensive medications belonging to different groups of the same category, significantly lowers blood pressure, in comparison with the effect produced by increasing the dose of a single medicament. Among the various analytical techniques employed for the estimation of Hydrochlorothiazide, the review portrays that hyphenated technique, in specific liquid chromatography coupled with mass spectroscopy was widely employed. The validation parameters namely linearity, LOD, LOQ for individual drug and their combinations, were successfully calibrated. The effectiveness of analytical approaches was evaluated and enhanced for chemical factors. The involvement of green chemistry in the optimized methods for the evaluation of Hydrochlorothiazide for the future development, are suggested.

Open access

Abstract

This review focuses on monosodium glutamate which proclaims the fifth taste as “Umami”. Monosodium glutamate imparts a deep, meaty, umami flavour to foods. Asian cuisine frequently uses this flavouring, just as in the processed items produced across the United States and Europe. This article dealt with a detailed discussion of physicochemical features, pharmacological actions, and different reported analytical methodologies for the estimation of monosodium glutamate. Monosodium glutamate is analyzed using a variety of techniques, including spectroscopy, chromatography, electrochemistry, electrophoresis, chemometrics, flow injection analysis, and biosensors. According to results of comparative research of analytical methodologies, high performance liquid chromatography (HPLC) is most widely used method for analyzing monosodium glutamate which surpasses the gas chromatographic (GC) approach. All of the reported methods are accurate, precise, cost-effective, and sensitive. The European Union defined monosodium glutamate as a food additive that is permitted in some foods, but is subject to quantitative limits. Consequently, this study provides the analyst with an accessible path to quantifying monosodium glutamate's content for use in the food and pharmaceutical industries.

Open access

Abstract

A straightforward, dependable, and quick RP-LC method for the analysis of abiraterone acetate in its dose form and human urine has been devised. With DAD detection, sensitivity was reported to be high. The LOD and LOQ of the procedure were deemed adequate. The suggested approach was exhaustively validated in accordance with ICH requirements, and the findings demonstrated that it was exact, accurate, selective, and sensitive for the analysis of this pharmaceutical. The chromatographic separation was realized using a X-Terra RP-18 (150 × 4.60 mm i.d. × 5 μm) column and a UV detector set at 255 and 267 nm. In addition, pK a values were calculated based on the relationship between the retention factor and the pH of the mobile phase. The influence of the composition of the mobile phase on the ionization constant was investigated by measuring the pK a at various acetonitrile–water combinations ranging from 50 to 70% (v/v).

Open access

Abstract

Lenalidomide is a drug that has immune-modulating, anti-angiogenic, and anti-inflammatory properties. In this study, we developed green HPLC and spectrophotometric methods to determine the concentration of lenalidomide in pure and pharmaceutical formulations. In the HPLC method, 10 mM potassium dihydrogen phosphate solution (pH: 2.0) and ethanol (50:50, V/V) were used as mobile phases, isocratic elution was applied at a flow rate of 1.0 mL min−1 and detection was made at 304 nm. In the spectrophotometric method, the spectral patterns of standard solutions in different solvents were comprehensively examined, the best spectra were obtained with ultrapure water, and a wavelength of 304 nm was selected for detection. Both methods have been validated according to ICH guidelines for various parameters. Correlation coefficients greater than 0.999 were determined for both methods in the concentration range of 5–30 μg mL−1. The developed methods were applied to commercial formulations, and comparisons of the results were made using the Student (t) test for means and the Fischer (F) test for standard deviations. No statistically significant difference was observed between the methods. The greenness evaluation of these methods was carried out using AGREE software. The developed methods are proposed as excellent environmental and operator-friendly alternatives for the quantification of Lenalidomide in pharmaceutical formulations.

Open access

Abstract

“Feed the global population and regenerate the planet.”

The conditions necessary for the implementation of the above commonly used slogan did not exist 10–15 years ago. We did not have access to the information and databases that would have allowed us to increase yields for the purpose of feeding the growing population. While increasingly meeting sustainability requirements and regenerating the Earth. Anthropocentrism, the belief that humans are superior to everything else, benefits humans by exploiting human greed and ignorance, which is a dead end for both individuals and societies. Only humans can ignore the dynamic equilibrium processes of nature and disregard the consequences that adversely affect future generations. Ecocentric agricultural practices have several prerequisites. It is important for the academic sphere to recognize its significance. Another fundamental challenge is the continuous monitoring of the production unit and its close and distant environment for the purpose of decision preparation using Big Data. The Internet of Things (IoT) is a global infrastructure that represents the network of physical (sensors) and virtual (reality) “things” through interoperable communication protocols. This allows devices to connect and communicate using cloud computing and artificial intelligence, contributing to the integrated optimization of the production system and its environment, considering ecocentric perspectives. This brings us closer to the self-decision-making capability of artificial intelligence, the practice of machine-to-machine (M2M) interaction, where human involvement in decision-making is increasingly marginalized. The IoT enables the fusion of information provided by deployed wireless sensors, data-gathering mobile robots, drones, and satellites to explore complex ecological relationships in local and global dimensions. Its significance lies, for example, in the prediction of plant protection. The paper introduces small smart data logger robots, including the Unmanned Ground Vehicles (robots) developed by the research team. These can replace sensors deployed in the Wireless Sensor Net (WSN).

Open access

Abstract

Hungary is a Central European country that is rich in medicinal and aromatic wild plant species; in rural livelihoods, the collection, use, process, and trade of these plants are traditionally important contributors. However, due to several recent changes touching the sector, the natural ecosystems, biodiversity, and collectors - who generally belong to poorer social groups – are affected negatively.

The paper aims to introduce the Hungarian herbal sector from a holistic perspective, including its economic, environmental, and human dimensions, with a particular focus on sustainability. In this context, the purpose of the article is to discover this field as comprehensibly as possible and present it from both theoretical and practical aspects. Another objective is to collect the best practices and feasible solutions from the field in connection with promoting a harmonious, as well as economically prosperous relationship between nature and local people. This integrated approach helps show the industry's strengths and advantages, as well as its weaknesses and challenges. Based on the findings, the paper attempts also to propose some recommendations for the future.

Open access

„Két lábbal a földön, avagy miként próbál a talajtan válaszokat adni a globális kihívásokra”

Beszámoló a HUN-REN ATK Talajtani Intézetének Magyar Tudomány Ünnepe előadónapjáról

Agrokémia és Talajtan
Author:
Kitti Balog
Restricted access
Progress in Agricultural Engineering Sciences
Authors:
Donald Bimpong
,
Lois Amponsah Adofowaa
,
Ama Agyeman
,
Abena Boakye
,
Ibok Nsa Oduro
,
Ellis William Otoo
, and
John-Lewis Zinia Zaukuu

Abstract

Peanut butter and yoghurt are targeted for adulteration intended at consumer deception. This study aimed to fingerprint and detect peanut butter and yoghurt adulteration with cassava flour and starch using Near Infrared Spectroscopy (NIRS) in a quasi-experimental approach. Ingredients for laboratory sample preparation were obtained from the Kumasi Metropolis. Peanut butter was adulterated at 1, 3, 5, 10, 15, 20% w/w and yoghurt at 0.25, 0.5, 1, 3, 5, 10, 15, 20, 25, 45, 50% w/w. Selected concentrations mimicked practices on the market. Marketed products were randomly sampled from six markets in the Kumasi Metropolis to validate the study models. Samples were scanned with a hand-held NIRS in triplicates. Chemometric (Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) and Partial Least Square Regression (PLSR) models) statistical methods were employed to develop classification and prediction models. Peaks with spectral bands such as 1050 , 1200 and 1450 nm were observed for peanut butter and 990–1100 nm, 1100–1200 nm and 1300–1408 nm were observed for yoghurt in the NIR spectrum. Some yoghurt brands were suspected of containing cassava starch, while Peanut butter from the different markets differed based on classification models. Cassava flour and starch concentrations were quantitatively predicted by PLSR with an R2 CV of 0.98 and an error of 0.9 g/100 g (low error).

Restricted access