SOP for tryptophan metabolite analysis of dried blood spots (DBS) via LC-QQQ

Gut microbiota is an important factor affecting human health. The tryptophan metabolites (anthranilate, indole-3-acetamide, indole-3-acetate, indole-3-aldehyde, indole-3-butyric acid, indole-3-lactic acid, L-kynurenine, L-tryptophan, N-acetyl tryptophan) perform important signalling and immunomodulatory functions, especially interaction of the innate immune system of the host with PXR or AHR xenobiotic receptors. This protocol describe preparation of dried blood spots (DBS) and quantitative/semiquantitative determination using LC-QQQ. Sample preparation of DBS is complementary to the protein analysis and thus allows the simultaneous determination of tryptophan metabolites and proteins in DBS.Research Infrastructure RECETOX RI (No LM2018121) financed by the Ministry of Education, Youth and Sports, and Operational Programme Research, Development and Innovation - project CETOCOEN EXCELLENCE (No CZ.02.1.01/0.0/0.0/17_043/0009632)