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Acta Chromatographica
Authors:
Feifei Lin
,
Runrun Wang
,
Jingye Du
,
Congcong Wen
,
Xianqin Wang
,
Yongxi Jin
, and
Lingjiu Shao

Abstract

Febrifugine, a potent quinazolinone compound derived from the Chinese herb Chang Shan (Dichroa febrifuga), exhibits diverse biological activities and has demonstrated anti-tumor effects by functioning as focal adhesion kinase (FAK) inhibitors. In this study, our objective was to establish a quantitative UPLC-MS/MS method and investigate the pharmacokinetic characteristics of febrifugine in rats following intravenous and oral administration routes. The rat tail vein was used for the collection of blood samples at designated time intervals following intravenous (2.0 mg kg−1) and oral (6.0 mg kg−1) administrations. Plasma samples were pretreated with acetonitrile as a protein precipitant and methylcytisine as an internal standard. Febrifugine concentration in rat plasma was determined using the UPLC-MS/MS method, and pharmacokinetic parameters were calculated using drug and statistics (DAS) software version for statistical analysis. The linear range of febrifugine in rat plasma was 1.5–1,500 ng mL−1, meeting the precision, recovery, and stability requirements for determination purposes. Febrifugine had a half-life (t1/2) of 3.2 ± 1.6 h after administered via intravenous route, while t1/2 was 2.6 ± 0.5 h after oral administration. The developed UPLC-MS/MS method is facile to operate while adhering to rigorous methodological verification standards, rendering it suitable for investigating the pharmacokinetics of febrifugine; and bioavailability was determined as 45.8%.

Open access

Abstract

This study presents the development and validation of a robust HPLC-UV method for the simultaneous detection and quantification of vitamin D2, vitamin D3, ergosterol, and 7-dehydrocholesterol in a single analytical run, adhering to ICH Q2 (R1) guidelines. Application of the HPLC-UV method to six vegetable oils demonstrated inherent vitamin D content and its enhancement under different radiation conditions. Oils were exposed to direct sunlight, UVA, and UVB radiation, with UVB showing the most significant impact on vitamin D levels. Notably, UVB exposure increased vitamin D3 in castor oil from 2.82 μg mL−1 to 4.29 μg mL−1 and vitamin D2 in mustard oil from 0.73 μg mL−1 to 1.89 μg mL−1. The findings highlight the potential of UVB radiation to convert vitamin D precursors to active forms more effectively than other radiation sources. This study provides a novel approach for naturally enriching vitamin D in vegetable oils, offering a promising strategy to mitigate vitamin D deficiencies in populations with limited sun exposure or dietary restrictions. The developed HPLC-UV method and resultant insights into the radiation-induced enhancement of vitamin D content in oils contribute valuable knowledge to nutritional science.

Open access

Abstract

Zanubrutinib (Brukinsa, BeiGene) is a FAD approved second-generation Bruton's tyrosine kinase inhibitor that has more selectivity and reduced off-target action, resulting in mitigated cardiotoxicity compared to ibrutinib. The target of this investigation was to establish a fast, precise, green, and extremely sensitive UPLC-MS/MS approach for quantifying the level of zanubrutinib (ZNB) in human liver microsomes (HLMs). The separation of ZMB and revumenib was achieved using C8 column and isocratic gradient of the mobile phase. The linearity of the constructed ZNB calibration curve was ranged from 1 to 3,000 ng mL−1. The StarDrop software package including DEREK and WhichP450 modules was used in screening for the toxic alerts the in silico metabolic lability of ZNB. The AGREE score was 0.76 that approves the greenness of the established method. The low in vitro t1/2 (17.61 min) and high intrinsic clearance (46.03 mL min−1 kg−1) of ZNB revealed that ZNB shares similarities with medications that have a high extraction ratio. The present LC-MS/MS approach is considered the first analytical methodology for assessment of ZNB metabolic stability in HLMs matrix. In silico data from WhichP450 and DEREK modules suggest that making small structural changes (bioisosteric replacement) to the carboxamide moiety during drug design can potentially improve the metabolic safety and stability of novel compounds relative to ZNB. These methods are essential for advancing the development of new pharmaceuticals, particularly in enhancing metabolic stability.

Open access

Abstract

Eleutherococcus senticosus (Rupr. & Maxim.) Maxim. fruits (ESF) is a natural health food that has been widely used in traditional medicine. This study aimed to establish and validate a rapid and sensitive method for determining of six phenolic acids in plasma of normal and T2DM rats by ultra-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS). Separation and quantification were performed on a Waters HSS T3 column (100 × 2.1 mm, 1.8 μm) with water (A) and methanol (B). The electrospray ionization (ESI) source was operated in negative ionization mode. Multiple reaction monitoring (MRM) was used to quantitatively analyzed hyperoside m/z 463.2→301.1, caffeic acid m/z 179.1→135.1, chlorogenic acid m/z 353.2→190.9, gallic acid m/z 169.0→125.1, protocatechuic acid m/z 153.1→109.1, and isofraxidin m/z 221.1→191.0, respectively. The hypoglycemic effect of ESF was verified by determining blood glucose and lipid levels in a type 2 diabetes model. This study laid the foundation for exploring ESF clinical guidelines in the future.

Open access

Abstract

High Performance Thin Layer Chromatography has capacity to run many samples simultaneously and its reduced solvent usage. Simultaneous quantification of gallic acid, ferulic acid, rutin and berberine in Asthimajja Pachak Kwath has been developed and validated using a specific, precise, accurate, and low-cost high performance thin layer chromatography technique. Toluene: ethyl acetate: chloroform: methanol: formic acid (5:2:2:2:1, v/v/v/v/v) was used as mobile phase during separation, which took place on a stationary phase of pre-coated silica gel aluminum plate 60 F254. At 270 nm, separated components were densitometrically measured. The method was validated for linearity and range, precision, reproducibility, specificity, robustness, accuracy, limit of detection and limit of quantification as per International Council for Harmonization Q2 (R2) guideline. Gallic acid, ferulic acid, rutin and berberine regression coefficients (R 2) were found to be 0.9995, 0.9990, 0.9985 and 0.9997 accordingly. Gallic acid, ferulic acid, rutin and berberine percentage recoveries were measured to be 99.81 ± 0.833, 99.15 ± 0.776, 99.56 ± 0.582 and 99.90 ± 0.719 respectively. Having a reliable analytical method is essential for ensuring the quality, consistency, and efficacy of herbal formulations in traditional medicine. This meticulous approach is crucial for accurate quantification of the target compounds in the Asthimajja Pachak Kwath.

Open access

Abstract

Nowadays, drone imagery is a common way to quickly obtain information on the state of vegetation, as well as a method for taking orthophotos and terrain models. For terrain modelling, aerial photographs are required to have at least 60% overlap between adjacent images. Typically, the inadequate overlap is only discovered later, during post-processing. In our previous work we have presented a method we developed to determine on the spot, whether the in-flight images are suitable for producing the terrain model or whether it is necessary to re-render a part of the area, which can be done under the same conditions (weather, ionosphere, satellite geometry). Our proposed method for calculating the overlap is different from the usual procedure. Using VBA-based calculations, we computed the overlap between the images based on the position of the centre of the images, the altitude of the flight and the rotation angle of the images. The method was tested in practice, but we felt it necessary to verify our calculations. During the verification, we checked the VBA-based calculations using a Python script. The test showed that the results obtained with a previous midpoint calculation method were 92.2 percent identical to the calculations performed with Python. The Python program is accurate and fast; therefore, the use is recommended on the field.

Open access
Progress in Agricultural Engineering Sciences
Authors:
József Zsembeli
,
Elza Kovács
,
Endre Harsányi
,
Péter Balogh
,
Péter Czine
,
László Huzsvai
,
Maria Bihuňová
,
Ján Jobbágy
,
Hana Středová
,
Milan Skalicky
,
Andrzej Strużyński
,
Roman Rolbiecki
, and
Csaba Juhász

Abstract

Similar to other regions, in East Central Europe, agriculture is the most vulnerable sector regarding the consequences of climate change through increasing variability in weather conditions, even on the short-term and local scales. Agricultural engineers make decisions; higher education has a crucial role in taking proper actions. Our survey aimed to get up-to-date information on the knowledge and attitude of graduating students completing agriculture-related studies at 6 universities located in Hungary, the Czech Republic, Poland, and Slovakia, with particular attention to weather projections, crop production, and soil protection issues. Analyses revealed adequate lexical knowledge of young engineers in each country. They are familiar with the agro-environmental actualities and future trends, issues to address at the right time, and the repertoire of tools and practices for taking efficient measures. A positive attitude toward proactive actions was proved. We report proof of a high level of preparedness resulting from the proper efficacy of agricultural higher education. The content of the curricula and the teaching methodologies meet well the receptiveness to learning in the V4 countries. Our findings confirm that frequent updating of the content of subjects as well as incorporating practical applications that promote active learning and engagement, are more critical today than ever, and it is possible to achieve a high level of preparedness for the challenges in the agricultural sector.

Open access