Liquid chromatography-mass spectrometry (LC-MS) using atmospheric pressure ionization is drastically different from hitherto available analytical methods used to detect polar analytes. The electrospray ionization (ESI) and atmospheric pressure chemical ionization (APCI) sources of MS have contributed to the advancement of LC-MS and LC-MS/MS techniques for the analysis of biological samples. However, one major obstacle is the weak ionization of some analytes in the ESI and APCI techniques. In this review, we introduce high-sensitivity methods using several derivatization reagents for ionization enhancement. We also present an overview of chemical derivatization methods that have been applied to small molecules, such as amino acids and steroids, in biological samples.
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http://dx.doi.org/10.1016/j.jchromb.2011.02.008 | DOI Listing |
Sensors (Basel)
December 2024
UFZ Helmholtz Centre for Environmental Research, Department Monitoring and Exploration Technologies, Permoserstraße 15, 04318 Leipzig, Germany.
Ion mobility spectrometry is successfully used as a sensor technology for different applications. A feature of this method is that characteristic ion mobility spectra are obtained for each measurement rather than a sum signal. The spectra result from the different drift velocities of ions in a drift tube at atmospheric pressure.
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December 2024
Institute of Chemistry, University of Miskolc, 3515 Miskolc-Egyetemváros, Hungary.
In this work, α-tocopherol and trolox were studied as compounds that have high biological activity. α-Tocopherol is considered a food additive because the refining process of vegetable oils causes the depletion of this vitamin, and thus, its inclusion is required to keep them from oxidizing. Computational tools have determined the antioxidant activity of these additives.
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December 2024
Department of Physical Chemistry and Biophysics, Faculty of Pharmacy, Wroclaw Medical University, Borowska 211A, 50-556 Wroclaw, Poland.
(1) Background: The aim of the work was to investigate the influence of selected physico-chemical factors on the solubility and release rate of CT (cryptotanshinone) in alcohologels. (2) Methods: The alcohologels of methylcellulose (MC), hydroksyethylcellulose (HEC), polyacrylic acid (PA) and polyacrylic acid crosspolymer (PACP) with CT were prepared and/or doped with native potato starch (SN) and modified citrate starches (SM2.5 and SM10).
View Article and Find Full Text PDFTalanta
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:
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) has become a robust tool for analyzing a variety of biomacromolecules. However, the strong background interference produced by conventional organic matrices hinders the detection of small molecule analytes, which restricts the widespread application of MALDI-MS in metabolomics studies. Consequently, developing new organic matrices is urgently needed to overcome these issues.
View Article and Find Full Text PDFMass Spectrom (Tokyo)
December 2024
Department of Pharmaceutical Engineering, Faculty of Engineering, Toyama Prefectural University, 5180 Kurokawa, Imizu-City, Toyama 939-0398, Japan.
Matrix-assisted laser desorption/ionization (MALDI), surface-assisted laser desorption/ionization (SALDI), and time-of-flight mass spectrometry (TOFMS) imaging are used for visualizing the spatial distribution of analytes. Mass spectrometry (MS) imaging of a sample with a rough surface with a uniform distribution of an analyte does not provide uniform ion intensities in the image. A shift in the value of the analyte ions is also observed.
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