Although chemical modification of analytes is a well-accepted adjunct to chromatography, little attention had been paid to the automation of pre-column derivatization techniques. An automated pre-column system would offer advantages when analyses are performed using labile derivatives; and also when the time between injections is long and so staff time spent on achieving maximum analytical outp...

A fast in-capillary derivatization method by CE with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate was developed for the first time for the determination of amino acid enantiomers (arginine, lysine, and ornithine) in dietary supplements and wines. Because of the initial current problems due to the formation of precipitates into the capillary during the derivatization reaction, a washing step ...

γ-Aminobutyric acid (GABA) is an inhibitory neurotransmitter having anti-anxiety, stress-reducing and sleep-enhancing effects. The blood GABA concentration has the potential to become a diagnostic index for depression schizophrenia. In this study, we developed method quantification of in human serum by liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) combine...

Introduction: A simple and reliable high performance liquid chromatographic method has been developed for the quantitative determination of pregabalin in bulk dosage form. Pregabalin, a γ amino butyric acid analogue, negligible sensitivity to UV or fluorescence detection. Hence, it derivatized by ninhydrin form chromophoric complex that could be quantified Materials Methods: The concentration w...

Agilent Bond Elut C18 gave the best results is this effective application of derivatizing aliphatic and biogenic amines on SPE versus solution derivatization. Published by Springer. Forensics and toxicology Development and validation of a gas chromatography-mass spectrometry method for the simultaneous determination of buprenorphine, flunitrazepam and their metabolites in rat plasma: applicatio...

A new combined gas chromatography and mass spectrometry (GC-MS) method has been developed suitable for the urine sample treatment in aqueous phase with ethyl chloroformate (ECF) derivatization agents. The method has been extensively optimized and validated over a broad range of different compounds and urine samples. Analysis of test metabolite derivatives, containing spiked standards, or rat ur...

An analytical method was set up suitable for the analysis of microbial metabolomes, consisting of an oximation and silylation derivatization reaction and subsequent analysis by gas chromatography coupled to mass spectrometry. Microbial matrixes contain many compounds that potentially interfere with either the derivatization procedure or analysis, such as high concentrations of salts, complex me...

Flow injection analysis coupled with membrane introduction mass spectrometry (FIA-MIMS) with on-line derivatization is shown to allow fast, accurate, nearly interference-free, and sensitive (low microgram/L) quantitation of phenolic compounds in water. On-line FIA derivatization of the phenolic compounds is performed by acetic anhydride acetylation in a K2CO3-buffered alkaline medium. The pheno...

15-series prostaglandins (PGE₂s) and isoprostanes (isoPGE₂s) are robust biomarkers of oxidative stress, possess potent biological activity, and may be derived through cyclooxygenase or free radical pathways. Thus, their quantification is critical in understanding many biological processes where PG, isoPG, or oxidative stress are involved. LC/MS/MS methods allow a highly selective, sensitive, si...

Dichlorprop is available for agricultural use as a chiral pesticide. In this study, the stereoselective determination of dichlorprop enantiomers in tea samples such as green, black, jasmine, and oolong was developed by ultra performance LC with fluorescence spectrometry after covalent chiral derivatization. The separation was achieved on an Acquity BEH C18 column with the mobile phase consistin...