Rationale: The offline coupling of high-performance thin-layer chromatography (HPTLC) with atmospheric solids analysis probe mass spectrometry (ASAP-MS) was evaluated for the characterization of polymeric additives in gasoline.
Methods: A protocol was developed to optimize the ion signal. A glass capillary was moistened with deionized water, and then dipped into silica gel scratched from an HPTLC plate. The capillary tube was fixed to the ASAP holder and introduced into the ionization source for analysis by MS. Silica gel, reversed-phase C18 and cellulose stationary phases were evaluated.
Results: The effect of the stationary phase and the nature of analyte were evaluated using polypropylene glycol and polyisobutylene succinimide polyamine as analyte molecules. The optimal ionization conditions are significantly different between ASAP and HPTLC/ASAP-MS analyses. In particular, a higher desorption gas temperature was required to produce ions from the silica gel HPTLC plate. The presence of the stationary phase reduces the internal energy of the ions and limits the fragmentation.
Conclusions: HPTLC/ASAP-MS is a very fast and efficient technique for the analysis of polymers in formulated fuels. Good ionization efficiency was obtained with all investigated stationary phases.
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http://dx.doi.org/10.1002/rcm.8755 | DOI Listing |
FEMS Microbes
December 2024
Manchester Institute of Biotechnology, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.
Bacteriological agar plates are commonly used to carry out experiments for the selective growth of microorganisms and the isolation of single-strain colonies. However, the presence of agar itself may be a confounding factor since it may serve as a source of carbon and energy. Moreover, there have been ongoing constraints on the production and sourcing of agar.
View Article and Find Full Text PDFJ Pharm Sci
January 2025
Nanotech Laboratory, Department of Pharmaceutics, National Institute of Pharmaceutical Education and Research (NIPER) Guwahati, Changsari, Kamrup 781101, Assam, India. Electronic address:
The application of mesoporous silica nanoparticles (MSN) as a drug carrier system got immense attention in the past few years due to their exceptional high drug loading efficiency. However, the process of drug loading is quite challenging compared to other lipid-based drug delivery systems. Hence, the MSNs using different catalysts were synthesized, and their mesoporous material characteristic was confirmed by the type IV adsorption-desorption isotherm using BET analyzer.
View Article and Find Full Text PDFAppl Radiat Isot
December 2024
Radiopharmacy Unit, Department of Pharmacy, Groupement Hospitalier Sud - Hospices Civils de Lyon, 165 chemin du Grand Revoyet, 69495, Pierre-Bénite, France; Department of Pharmacy - Groupement Hospitalier Sud - Hospices Civils de Lyon, 165 chemin du Grand Revoyet, 69495, Pierre-Bénite, France.
For hepatobiliary scintigraphy, the radiopharmaceutical drug, ETIFENIN (TECHIDA®), labelled with technetium-99m, is used as a substitute for MEBROFENIN (CHOLEDIAM®). It is generally accepted that radiopharmaceuticals should be checked prior to injection, in particular by determining radiochemical purity, to ensure high-quality images. Radiochromatographic techniques or methods described in the Summary of Product Characteristics (SmPC) and the European Pharmacopeia (Ph.
View Article and Find Full Text PDFZhongguo Zhong Yao Za Zhi
December 2024
Engineering Research Center for Industrialization of Southern Medicinal Plants Resources of Hainan Province, Hainan Normal University Haikou 571158, China Key Laboratory of Southern Medicinal Plants Resources of Haikou City, Hainan Normal University Haikou 571158, China Key Laboratory of Tropical Medicinal Resource Chemistry of Ministry of Education, Hainan Normal University Haikou 571158, China.
The chemical constituents from the stems and leaves of Mycetia hainanensis were isolated by silica gel, ODS gel, and Sephadex LH-20 gel column chromatography and preparative HPLC. The chemical structures of all the isolated compounds were identified on the basis of their physicochemical properties, spectroscopic data, as well as the comparison of their physicochemical and spectroscopic data with the reported data in literature. Twelve compounds were isolated from the 85% ethanol extract of the stems and leaves of M.
View Article and Find Full Text PDFSoft Matter
January 2025
Faculty of Science and Letters, Department of Chemistry, Soft Materials Research Laboratory, Istanbul Technical University, Istanbul, Maslak, 34469, Turkey.
A series of anionic poly(acrylamide--sodium acrylate)/poly(ethylene glycol), PAN/PEG, hybrids were conveniently synthesized free radical aqueous polymerization by integrating bentonite, kaolin, mica, graphene and silica, following a simple and eco-friendly crosslinking methodology. A comparative perspective was presented on how integrated nanofillers affect the physicochemical properties of hybrid gels depending on the differences in their structures. Among the five types of nanofillers, bentonite-integrated hybrid gel had the highest water absorbency, while graphene-integrated gel had the lowest.
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