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, r2 > 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.