RESUMO
Hair is increasingly used as a biological matrix of interest for the assessment of hormone secretion over extended periods of time. This study described the development and the validation of a sensitive UPLC-MS/MS method for simultaneous analysis of steroid and thyroid hormones in human hair. The gradient designed in this method enables to obtain a satisfactory separation of 9 hormones of interest: cortisol, cortisone, THE, THF, α-THF, triiodothyronine (T3) and thyroxine (T4), estradiol, and testosterone. Several methodological parameters of extraction (such as the used of "cut hair" versus "pulverized hair", the extraction time, the incubation solvent purification on SPE column and hydrolysis) that may influence the determination of hormones levels in human hair, have thus been tested here. Therefore, the results obtained highlighted the necessity of using a C18 SPE purification method for the determination of both steroid and thyroid hormones in hair. This method allows reaching suitable levels of sensitivity for cortisol and cortisone since the results obtained pointed out concentration levels of cortisol in hair of volunteers similar to those observed in the literature. This method could also offer an important impact in the field of hormone analysis since it allows, for the first time, the quantification of both T3 and T4 in human hair.