LAUSR

Urocanic acid is a chromophore found in the skin that has been identified as an important immunosuppressant and carcinogenesis mediator through its photoisomerization from trans to cis form induced by ultraviolet radiation. Research on analytical methods that explore urocanic acid isomerization is indispensable to fully understand the deleterious effects mediated by this biomarker. In this context, the current relevant analytical methods for determination of these isomers in human samples are summarized in this review. The methods presented here are applicable to human samples collected by non-invasive methods (or minimally invasive), encompassing an array of analytical techniques, including HPCE, confocal Raman spectroscopy, GC, HPLC and MS, among others. Developed HPLC methods have proven to be advantageous, allowing non-invasive collections for in vivo analysis and the confocal Raman, specially, for real-time analysis. Among all these methods, HPLC is the most investigated one with MS or ultraviolet detector, and the MS detector being the most studied in the last years, demonstrating high sensitivity, very low detection limits, and accurate identification, especially to clinical investigations. This article is protected by copyright. All rights reserved.