《A validated UHPLC-MS method for tryptophan metabolites: Application in the diagnosis of multiple sclerosis》 was written by Tomosi, Ferenc; Kecskemeti, Gabor; Cseh, Edina Katalin; Szabo, Elza; Rajda, Cecilia; Kormany, Robert; Szabo, Zoltan; Vecsei, Laszlo; Janaky, Tamas. Application of 98-98-6This research focused onUHPLC mass spectrometry tryptophan metabolite diagnosis multiple sclerosis; Derivatization; DryLab®4; Liquid chromatography-mass spectrometry; Multiple sclerosis; Tryptophan metabolism; Validation. The article conveys some information:
The simultaneous quant. estimation of tryptophan (TRP) and its metabolites represents a great challenge because of their diverse chem. properties, e.g., presence of acidic, basic, and nonpolar functional groups and their immensely different concentrations in biol. matrixes. A short ultra high-performance liquid chromatog. (UHPLC)-tandem mass spectrometry (MS/MS) method was validated for targeted anal. of TRP and its 11 most important metabolites derived via both kynurenine (KYN) and serotonin (SERO) pathways in human serum and cerebrospinal fluid (CSF): SERO, KYN, 3-hydroxyanthranilic acid, 5-hydroxyindoleacetic acid, anthranilic acid, kynurenic acid (KYNA), 3-hydroxykynurenine (3-HK), xanthurenic acid, melatonin, picolinic acid (PICA), and quinolinic acid (QUIN). After selecting the “”best”” reversed-phase column and organic modifier, DryLab4 was used to optimize the gradient time and temperature in chromatog. separation To achieve absolute quantification, deuterium-labeled internal standards were used. Among all compounds, 3 were analyzed in derivatized (Bu ester) forms (3-HK, PICA, and QUIN) and the remaining 9 in underivatized forms. Validation was performed in accordance with the ICH and FDA guidelines to determine the intraday and interday precision, accuracy, sensitivity, and recovery. To demonstrate the applicability of the developed UHPLC-MS/MS method, the aforementioned metabolites were analyzed in serum and CSF samples from patients with multiple sclerosis (multiple sclerosis group) and those with symptomatic or noninflammatory neurol. diseases (control group). The concentration of QUIN dramatically increased, whereas that of KYNA slightly decreased in the multiple sclerosis group, resulting in a significantly increased QUIN/KYNA ratio and significantly decreased PICA/QUIN ratio. In the part of experimental materials, we found many familiar compounds, such as Picolinic acid(cas: 98-98-6Application of 98-98-6)
Picolinic acid(cas: 98-98-6) is used as a chelate for alkaline earth metals. Used to prepare picolinato ligated transition metal complexes. In synthetic organic chemistry, has been used as a substrate in the Mitsunobu reaction and in the Hammick reaction.Application of 98-98-6