Bar adsorptive microextraction for the qualitative detection of cocaine and its metabolites in urine for anti-doping control

Anti-Doping laboratories face ongoing challenges due to the continuous emergence of new drugs. To meet the stringent technical requirements of the World Anti-Doping Agency (WADA), laboratories must enhance their operational procedures. The Bar Adsorptive MicroExtraction (BAμE), a modern technique aligned with the green analytical chemistry and successfully applied to various matrices, represents a promising alternative in the anti-doping context. The BAμE was applied for the qualitative identification of Cocaine and three metabolites (BenzoylecGonine, ecGonine Methyl Ester and Cocaethylene) in human urine, followed by derivatization and gas chromatography–mass spectrometry analysis. Using optimized conditions, the method provided limits of identification of 1.0–10.0 ng/mL, linear calibration curves of 1.0–200.0 ng/mL, r 2 > 0.9950, extraction recoveries of 39.4%–71.1%, with high selectivity, robustness, accuracy and precision. Five urine samples were successfully assayed, with unequivocal detection of several target compounds. The BAμE-based methodology was successfully applied for the first time to anti-doping control of cocaine in human urine, providing high selectivity, sensitivity, and reduced interferences with minimal toxic solvent use. The BAμE(P3)-μLD/GC–MS(SIM) approach is cost-effective, user/eco-friendly, and fit-for-purpose as it complies with all WADA technical requirements.