IN-HOUSE VALIDATION OF METHYLTESTOSTERONE DETERMINATION IN NATURAL WATERS BY VOLTAMMETRY USING HANGING MERCURY DROP ELECTRODE

摘要

17?±-methyltestosterone (17?±-MT) is a hormone used in medicine and aquaculture which can be found in natural waters. It is considered an emerging organic pollutant and its accurate and precise analysis is required. Therefore, this study presents the in-house validation of a new voltammetric methodology for 17?±-MT analysis in natural waters. A hanging mercury drop electrode and NaOH 5.0?—10-3 mol L-1 solution as the electrolyte were employed in the voltammetric determinations. To confirm the presence of 17?±-MT in water samples quantitative analysis was performed by ESI-MS/MS. The methodology exhibited good selectivity, linearity, accuracy (recovery of between 100.4 and 108.8%) and precision (RSDs for repeatability of 2.85% and for intermediate precision of 14.10%, with n = 5, respectively). LOD and LOQ were 3.07 ?μg L-1 and 10.78 ?μg L-1, respectively. The methodology was suitable for determination of 17?±-MT in natural waters due to low-cost, good performance and no sample pre-treatment required.