The RP HPLC method (LiChrosorb RP18 or Separon SGX C18 column, acetonitrile-water 86:14 v/v mobile phase) was applied for enantiomeric separation of topologically chiral 5-bromo-25,26-bis(diethoxyphosphoryl)calix[4]arene 9 or 25-ethyl-26-dihydroxyphosphoryl-calix[4]arene 5. Separation of calixarene 9 was achieved by the addition of D-(-)-tartaric acid which formed hydrogen bonded diastereomeric associates with 9 to the mobile phase. Calixarenephosphoric acid 5 was transformed into diastereomeric salt 6 by addition of L-(-)-alpha-phenylethylamine before RP HPLC separation.
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Chirality
February 2025
Daicel Chiral Technologies, West Chester, Pennsylvania, USA.
The influence of additives and modifiers on the chiral HPLC separation of the nicotine enantiomers using UV/Vis detection is discussed. Selected alcohols as modifiers and selected amines as additives were found to have a significant effect on the resolution and retention times of nicotine enantiomers even to the point of eliminating component elution. Systematic variations in the concentration of ethanol, methanol, and isopropanol, as modifiers, along with variations in the concentration of diethylamine, triethylamine, tributylamine, ethylenediamine, isopropylamine, as additives, revealed that the average resolution (R) of the nicotine enantiomers ranged from 2.
View Article and Find Full Text PDFEnviron Sci Pollut Res Int
January 2025
Animal Production Department, Faculty of Agriculture, Cairo University, Giza, Egypt.
Aquaculture systems generate large amounts of sludge that represent serious environmental threats if discharged directly into local ecosystems. However, this nutrient-rich sediment can contribute to nutrient cycling by being applied as an organic fertilizer to ornamental medicinal trees during their early growth stages. To investigate the potential advantages of using recirculating aquaculture system sludge (RASS) and biofloc technology sludge (BFTS) as organic fertilization alternatives to chemical fertilization, a pot trial was conducted at the Faculty of Agriculture, Cairo University, Egypt.
View Article and Find Full Text PDFJ Ethnopharmacol
January 2025
State Key Laboratory of Natural Medicines, China Pharmaceutical University, Nanjing, 211198, China; Jiangsu Key Laboratory of TCM Evaluation and Translational Research, China Pharmaceutical University, Nanjing, 211198, China. Electronic address:
Ethnopharmacological Relevance: Cholestatic liver injury (CLI) is a pathophysiological syndrome characterized by the accumulation of bile acids (BAs), which leads to significant hepatic dysfunction. This condition is frequently associated with disturbances in BAs homeostasis and the induction of oxidative stress. Ribes diacanthum Pall (RDP), a conventional folk medicinal plant, has been employed in Mongolia, the Inner Mongolia region of China, and other areas for the remediation of hepatic disorders.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
Ministry of Education Key Laboratory of Analytical Science for Food Safety and Biology, Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food Safety, College of Chemistry, Fuzhou University, Fuzhou, Fujian, 350108, China. Electronic address:
Benzophenone derivatives (BPs), as synthetic chemicals widely used in personal care products, have drawn increasing attention due to their potential health risks. However, monitoring BPs in biological samples remains challenging due to their complex matrices and the deficiency in sensitivity and selectivity in current methods. Herein, a method combining hierarchically flower-like hollow covalent organic frameworks (HFH-COFs) with high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was established for the enrichment and detection of BPs in serum samples.
View Article and Find Full Text PDFTalanta
January 2025
School of Pharmacy, Shenyang Pharmaceutical University, Shenyang, 110016, PR China. Electronic address:
Monitoring of p-nitrophenol (PNP) and 3-methyl-4-nitrophenol (PNMC) in human urine and environmental water is of great importance for human health assessment and environmental protection, as they are both urinary metabolites of some poisonous pesticides and priority environmental pollutants. However, efficient extraction of trace levels of PNP and PNMC from complex matrices remains challenging. This study presented the synthesis of histidine-modified ZIF-90 on natural eggshell membrane (ESM@His-ZIF-90) via a facile one-step in-situ growth strategy, and its application as an adsorbent for dispersive membrane extraction (DME) of PNP and PNMC in human urine and environmental water.
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