Fluorometric Determination of L-Kynurenine with Glycolaldehyde by High Performance Liquid Chromatography
L-Kynurenine (KYN) is one of the metabolites of L-tryptophan(Trp) on the kynurenine pathway. The first step of the kynurenine pathway is an oxidative cleavage of the indole ring of Trp, which is catalyzed by tryptophan 2, 3-dioxygenase (EC 22.214.171.124, TDO) to form N-formyl-L-kynurenine. In mammalian system, TDO is found only in liver and N-formyl-L-kynurenine is hydrolyzed instantly to KYN by an excess of formamidase present in liver. Therefore, in many cases assay of the TDO activity is based on the determination of KYN formed by TDO. We have developed a new fluorometric method for the determination of KYN by a single-pump high performance liquid chromatography (HPLC) using glycolaldehyde(GLA) as fluorogenic reagent. The method was successfully applied to the assay of the TDO activity.
KeywordsHigh Performance Liquid Chromatography Tryptophan Epinephrine Disodium Phan
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