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J Chromatogr Sci
January 2025
Division of Chemical and Material Metrology, Korea Research Institute of Standards and Science, 267, Gajeong-ro, Yuseong-gu, Daejeon, 34113Republic of Korea.
We developed a reversed-phased high-performance liquid chromatographic method combining ultraviolet detection and integrated pulsed amperometric detection for the simultaneous quantification of dopamine, 5-hydroxyindolacetic acid, homovanillic acid, serotonin, 3,4-dihydroxyphenylacetic acid, norepinephrine and epinephrine. All target components were completely separated in a C18 column with isocratic elution of 5% acetonitrile solution containing 8 mM HClO4 and 0.20 mM 1-octanesulfonic acid as an ion pairing reagent.
View Article and Find Full Text PDFMethods Mol Biol
January 2025
Laboratory of Analytical Biochemistry & Metabolomics, Biology Centre, Czech Academy of Sciences, České Budějovice, Czech Republic.
A simple analytical workflow is described for gas chromatographic-mass spectrometric (GC-MS)-based chiral profiling of secondary amino acids (AAs) in biological matrices. The sample preparation is carried out directly in aqueous biological sample extracts and involves in situ heptafluorobutyl chloroformate (HFBCF) derivatization-liquid-liquid microextraction of nonpolar products into hexane phase followed by subsequent formation of the corresponding methylamides from the HFB esters by direct treatment with methylamine reagent solution. The (O, N) HFB-butoxycarbonyl-methylamide AA products (HFBOC-MA) are separated on a Chirasil-L-Val capillary column and quantitatively measured by GC-MS operated in selected ion monitoring (SIM) mode.
View Article and Find Full Text PDFBMC Chem
January 2025
Department of Pharmaceutical Analytical Chemistry, Faculty of Pharmacy, University of Alexandria, Elmessalah, Alexandria, 21521, Egypt.
A simple, rapid, and reproducible high-performance liquid chromatography (HPLC) method has been developed and validated for the determination of β-sitosterol in the pharmaceutical dosage form of moist exposed burn ointment (MEBO). This method involved an effective sample procedure for extraction of β-sitosterol from MEBO using an alkali saponification agent composed of 0.8 N ethanolic NaOH and diethyl ether.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
December 2024
Xinjiang Key Laboratory of Clean Conversion and High Value Utilization of Biomass Resources,School of Chemistry and Chemical Engineering, Yili Normal University Yining 835000, China School of Health, Jiangxi Normal University Nanchang 330022, China.
Ten compounds were separated by various modern chromatographic methods from mastic. They were identified by HR-ESI-MS, IR, UV, NMR, quantum chemical calculation of NMR(qcc-NMR) and comparison with reported data in literature as 17β-hydroxy-28-norolean-18-en-3-one(1), 28-norolean-12,17-dien-3,11-dione(2), 28-norolean-16,18-dien-3-one(3),(24Z)-26-hydroxy-7,24-dientirucalla-3-one(4), masticadienonic acid(5)、masticadienolic acid(6)、erythrodiol(7), 3β,28-dihydroxyoleana-11,13(18)-diene(8), 3-oxo-olean-9(11),12-dien-28-oic acid(9), and 12-oleane-3,11-dione(10). Among them, compound 1 was a novel compound and compound 2 was a novel natural product.
View Article and Find Full Text PDFJ Chromatogr A
January 2025
School of Pharmaceutical Sciences, University of Geneva, CMU - Rue Michel Servet 1, 1211 Geneva 4, Switzerland; Institute of Pharmaceutical Sciences of Western Switzerland, University of Geneva, CMU - Rue Michel Servet 1, 1211 Geneva 4, Switzerland. Electronic address:
Ion exchange chromatography (IEX) is an important analytical technique for the characterization of biotechnology-derived products, such as monoclonal antibodies (mAbs) and more recently, cell and gene therapy products such as messenger ribonucleic acid (mRNA) and adeno-associated viruses (AAVs). This review paper first outlines the basic principles and separation mechanisms of IEX for charge variant separation of biotherapeutics, and examines the different elution modes based on salt or pH gradients. It then highlights several recent trends when applying IEX for the characterization of biotechnology-derived products, including: i) the effective use of pH gradients, ii) the improvement of selectivity by using organic solvents in the mobile phase, multi-step gradients, or by combining ion pairing and ion exchange, and iii) the increase in analytical throughput using ultra-short columns or automated screening of conditions.
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