Kynurenine, the first product of tryptophan degradation via the kynurenine pathway, has become one of the most frequently mentioned biomarkers in recent years. Its levels in the body indicate the state of the human physiology. Human serum and plasma are the main matrixes used to evaluate kynurenine levels and liquid chromatography is the dominant technique for its determination. However, their concentrations in blood do not always correspond to the levels in other matrixes obtained from the affected individuals. It is therefore important to decide when it is appropriate to analyse kynurenine in alternative matrices. However, liquid chromatography may not be the best option for the analysis. This review presents alternatives that can be used and summarizes the features that need to be considered prior to kynurenine determination. Possible approaches to kynurenine analysis in a variety of human matrixes, their challenges, and limitations are critically discussed.

The Department of Analytical Chemistry Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 8 50005 Hradec Králové Czech Republic

The Department of Analytical Chemistry Faculty of Pharmacy in Hradec Králové Charles University Akademika Heyrovského 1203 8 50005 Hradec Králové Czech Republic; The Department of Clinical Biochemistry and Diagnostics University Hospital Hradec Králové Sokolská 581 50005 Hradec Králové Czech Republic

References provided by Crossref.org

Urinary kynurenine,tryptophan, and neopterin concentrations during physiological pregnancy