Accurate quantitation of compounds in samples of biological origin is often hampered by matrix interferences one of which occurs in GC-MS analysis from the presence of highly abundant phosphate. Consequently, high concentrations of phosphate need to be removed before sample analysis. Within this context, we screened 17 anion exchange solid-phase extraction (SPE) materials for selective phosphate removal using different protocols to meet the challenge of simultaneous recovery of six common organic acids in aqueous samples prior to derivatization for GC-MS analysis. Up to 75% recovery was achieved for the most organic acids, only the low pKa tartaric and citric acids were badly recovered. Compared to the traditional approach of phosphate removal by precipitation, SPE had a broader compatibility with common detection methods and performed more selectively among the organic acids under investigation. Based on the results of this study, it is recommended that phosphate removal strategies during the analysis of biologically relevant small molecular weight organic acids consider the respective pKa of the anticipated analytes and the detection method of choice.
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http://dx.doi.org/10.1016/j.chroma.2015.01.093 | DOI Listing |
J Agric Food Chem
January 2025
State Key Laboratory of Coordination Chemistry, Key Laboratory of Mesoscopic Chemistry (Ministry of Education), School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Facile pesticide nanocapsules were successfully prepared by directly encapsulating the antisolvent precipitation of pesticides through instantaneous "on site" coordination assembly of tannic acid and Fe, avoiding tedious preparation, time consumption, and large amounts of organic solvents. The pesticide nanocapsules showed excellent resistance to ultraviolet photolysis and rainwater washing owing to the nanocapsule walls. The smart pesticide nanocapsules exhibited the controlled release of pesticides under multidimensional stimuli, such as acidic/alkaline pH, glutathione, HO, phytic acid, laccase, tannase, and sunlight, which were related to the physiological and natural environments of crops, pests, and pathogens.
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Chemistry, The University of Chicago, Chicago, Illinois 60637, United States.
Luminescent chiral metal-organic frameworks (CMOFs) are promising candidates for the enantioselective sensing of important chiral molecules. Herein, we report the synthesis and characterization of Zn and Cd CMOFs based on 1,1'-bi-2-naphthol (BINOL)-derived 3,3',6,6'-tetra(benzoic acids), H-OEt and H-OH. Four CMOFs, -OEt, -OH, -OEt, and -OH, based on these ligands were crystallographically characterized.
View Article and Find Full Text PDFInt J Syst Evol Microbiol
January 2025
Department of Microorganisms, Leibniz Institute DSMZ German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.
An obligately anaerobic, spore-forming sulphate-reducing bacterium, strain SB140, was isolated from a long-term continuous enrichment culture that was inoculated with peat soil from an acidic fen. Cells were immotile, slightly curved rods that stained Gram-negative. The optimum temperature for growth was 28 °C.
View Article and Find Full Text PDFOrg Biomol Chem
January 2025
Key Laboratory of Green Chemical Process of Ministry of Education, Hubei Key Laboratory of Novel Chemical Reactor and Green Chemical Technology, School of Chemical Engineering & Pharmacy, Wuhan Institute of Technology, Wuhan 430073, P.R. China.
Electrochemical oxidative cross-dehydrogenative-coupling (CDC) is an ideal strategy to conduct the C3-alkoxylation of imidazo[1,2-]pyridine, but it remains a challenge owing to limitation imposed by the use of alkyl alcohols and carboxylic acids. Herein, we report a mild and efficient 2-electrode constant-potential electrolysis of imidazo[1,2-]pyridine with hexafluoroisopropanol (HFIP) to produce various imidazo[1,2-]pyridine HFIP ethers. Mechanistic studies indicated that the electrooxidation reaction might involve radical coupling and ionic reaction.
View Article and Find Full Text PDFAstrobiology
January 2025
Experimental Biophysics and Space Sciences, Department of Physics, Freie Universitaet Berlin, Berlin, Germany.
The (PSS) experiment was part of the European Space Agency's mission and was conducted on the International Space Station from 2014 to 2016. The PSS experiment investigated the properties of montmorillonite clay as a protective shield against degradation of organic compounds that were exposed to elevated levels of ultraviolet (UV) radiation in space. Additionally, we examined the potential for montmorillonite to catalyze UV-induced breakdown of the amino acid alanine and its potential to trap the resulting photochemical byproducts within its interlayers.
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