This work investigated the repeatability of column preparation for a reversed-phase C18 monolith, namely stearyl methacrylate-co-ethylene glycol dimethacrylate (SMA-EDMA). The columns were thermally polymerised using three commonly available heating devices (GC oven, hot air oven and water bath) and their chromatographic performance evaluated using micro-liquid chromatography for separation of five test compounds. Precision in terms of %RSD of retention times were 9.0, 6.5, and 12.5 using GC oven, hot air oven and water bath, respectively. Between-batch precision for the hot air oven (n=3 days) was less than 10.4% for retention time. The SMA-EDMA monolith was applied to the separation of tocopherol homologues by capillary electrochromatography. Usually tocopherol homologues cannot be completely separated by conventional reversed-phase C8- or C18-packed bed or C18-silica based monolithic columns. Polymer monolith has been shown to give remarkable selectivity towards the tocopherols compared to the conventional microparticulate phase and silica based monolith. Successful separation of the tocopherol isomers was achieved on the SMA-EDMA monolith without any column modification.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.talanta.2011.03.083 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
In Situ Column Modification of Silica Monoliths With Pentafluorophenyl Ligands for the HPLC Separation of Eight Tocochromanols.
J Sep Sci
December 2024
Department of Chromatography and Mass Spectrometry, Institute of Horticulture, Dobele, Latvia.
Silica-based monoliths offer higher separation efficiency per unit pressure drop compared to particle-packed columns. Their application is limited by the commercial availability of different column chemistries. Pentafluorophenyl ligands enable hydrogen bonding, dipole-dipole, π-π, and hydrophobic interactions, facilitating the separation of various compounds.
View Article and Find Full Text PDFA New LC-MS/MS-Based Method for the Simultaneous Detection of α-Tocopherol and Its Long-Chain Metabolites in Plasma Samples Using Stable Isotope Dilution Analysis.
Pharmaceuticals (Basel)
October 2024
Department of Nutritional, Food and Consumer Sciences, Fulda University of Applied Sciences, 36037 Fulda, Germany.
Our study presented a novel LC-MS/MS method for the simultaneous quantification of α-tocopherol (α-TOH) and its phase II metabolites, α-13'-COOH and α-13'-OH, in human serum using deuterium-labeled internal standards (d-α-TOH, d-α-13'-COOH, d-α-13'-OH). The method addresses the analytical challenge posed by the significantly different concentration ranges of α-TOH (µmol/L) and its metabolites (nmol/L). Previous methods quantified these analytes separately, which caused an increase in workflow complexity.
View Article and Find Full Text PDFSupercritical CO Fluid Extraction and Microencapsulation of Oil from Anchovy () By-Products.
Food Technol Biotechnol
September 2024
Faculty of Food Science and Engineering, Dunarea de Jos University of Galati, 111 Domnească Street, 800201 Galați, Romania.
Research Background: Fish by-products are discarded as waste, which has a significant impact on the environment. They have no economic value, but there are many opportunities to turn them into high value products. Due to significant quantities generated internationally and the continuous expansion of the market for ω-3 and ω-6 fatty acids as nutraceuticals, innovative technological approaches are needed to transform this waste into marketable products with added value, while limiting the risk of environmental pollution.
View Article and Find Full Text PDFSeminal oxidative stress index can be used as a marker in the prediction of bull semen cryotolerance.
Anim Reprod Sci
November 2024
Department of Biochemistry, Faculty of Veterinary Medicine, Ankara University, Ankara, Turkey. Electronic address:
In this study, it was aimed to evaluate the effect of seminal plasma activity levels of enzymatic antioxidants such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GPx), non-enzymatic antioxidant alpha-tocopherol (Vit-E), and also total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI) on post-thaw sperm quality. As well as it was aimed to investigate the possibility of the use of OSI as a marker for the estimation of bull semen freezability. For this study, 72 ejaculates were collected from 6 bulls and separated into two aliquots.
View Article and Find Full Text PDFPotentiometry in determining the antioxidant capacity of compounds of different hydrophilicity in the joint presence using mixed solvents and surfactants.
Anal Sci
December 2024
Chemical Technological Institute, Ural Federal University named after the First President of Russia B. N. Yeltsin, 19 Mira St, Ekaterinburg, Russian Federation, 620002.
In this work, for the first time, the potentiometric method was used to determine the antioxidant capacity (AOC) of compounds of different hydrophilicity in the joint presence using mixed solvents and surfactants. The AOC of model solutions of antioxidants of different hydrophilicity was determined separately and in the joint presence in the media of phosphate buffer-surfactant and mixed solvents-surfactant, using as an example the ascorbic acid and the α-tocopherol. It was shown that the surfactant Triton X-100 is able to solubilize α-tocopherol under the selected conditions, allows to obtain reproducible and accurate results, and has less effect on the equilibrium rate of the K[Fe(CN)]/K[Fe(CN)] system.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!