The chiral recognition mechanism for a series of d,l phenoxypropionic acid herbicides (PPAs) on a teicoplanin stationary phase was investigated in reversed phase liquid chromatography (RPLC) over a wide range of mobile phase pH and column temperature. The effect of methanol on the enantiomeric separation was studied by varying its fraction (v/v) in the mobile phase. The thermodynamic data indicated that the chiral recognition was controlled by the interaction between the anionic form of the solute and the teicoplanin phase while those with the neutral form played a minor role. In addition, it was demonstrated that the enhancement of the separation factor observed as the methanol fraction increased in the mobile phase was enthalpically controlled owing to stereoselective binding interactions. Such behavior was used to optimize the chromatographic conditions for separation of PPAs herbicides on teicoplanin.
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http://dx.doi.org/10.1016/s0039-9140(02)00450-2 | DOI Listing |
J Pharmacol Toxicol Methods
January 2025
Department of Pharmacy, the First Affiliated Hospital, Sun Yat-sen University, Guangzhou, China; Department of Gastroenterology, the Sixth Affiliated Hospital, Sun Yat-sen University, Guangzhou, China. Electronic address:
Background: Upadacitinib is a selective Janus kinase (JAK) 1 inhibitor approved by the Food and Drug Administration for the treatment of moderate-to-severe inflammatory bowel disease (IBD). We aimed to establish and validate a method for determining Upadacitinib in patients with IBD by liquid chromatography-tandem mass spectrometry (LC-MS/MS) method.
Methods: The mobile phase was 0.
Br J Nurs
January 2025
Department of Psychology, Faculty of Arts, University of Calgary, Alberta, Canada; Community Health Sciences, Faculty of Medicine, University of Calgary, Alberta, Canada; Ward of the 21st Century, Cumming School of Medicine, University of Calgary, Alberta, Canada.
Introduction: Peripheral intravenous cannulation (PIVC) is a common and complex procedure with low first-attempt success rates, causing patient suffering and increased healthcare costs. Quiet Eye (QE) training, a gaze-focused approach, has shown promise in improving procedural PIVC skills. We will examine the effectiveness of traditional technical training (TT) and QE training (QET) on student nurse PIVC performance.
View Article and Find Full Text PDFAge Ageing
January 2025
Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.
Background: A mobile cognition scale for community screening in cognitive impairment with rigorous validation is in paucity. We aimed to develop a digital scale that overcame low education for community screening for mild cognitive impairment (MCI) due to Alzheimer's disease (AD) and AD.
Methods: A mobile cognitive self-assessment scale (CogSAS) was designed through the Delphi process, which is feasible for the older population with low education.
Nat Prod Res
January 2025
College of Pharmacy, Guangxi Key Laboratory of Zhuang and Yao Ethnic Medicine, Guangxi University of Chinese Medicine, Nanning, China.
(L.) Jacq. has anti-inflammatory, analgesic, haemostatic and antioxidant effects, but its pharmacological components are still unclear.
View Article and Find Full Text PDFAnal Bioanal Chem
January 2025
Laboratory for Food Safety, French Agency for Food, Environmental and Occupational Health & Safety (ANSES), Université Paris-Est, 94700, Maisons-Alfort, France.
This study presents the development and validation of a precise analytical method for the speciation analysis of arsenic (As) compounds, including inorganic species [As(III) and As(V)] and organic species such as monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). The method employs anion-exchange high-performance liquid chromatography (AE HPLC) coupled with inductively coupled plasma-mass spectrometry (ICP-MS). To optimize the sample preparation process, microwave-assisted extraction (MAE) and heat-assisted extraction (HAE) techniques were evaluated and compared.
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