Comparison of the Modified QuEChERS Method and the Conventional Method of Extraction in Forensic Medicine to Detect Methadone in Post-Mortem Urine by GCMS

Background:Extraction of drugs is one of the biggest concerns and the most important part of preparation and determination in forensic medicine. The lack of an easy, efficient and fast extraction method is the most important and most difficult problem despite the development of forensic centers and their being equipped with new diagnostic devices. In the present study, a comparison was conducted between extraction of methadone in post-mortem urine (Autopsy), using modified QuEChERS method and conventional liquid-liquid extraction method in forensic medicine. Method: Methadone extraction from the Post-Mortem urine sample was performed using QuEChERS extraction method, which is a simple and fast micro-extraction method in tube. In this method, the analyte was extracted using MgSO4, NaCl salts and ethyl acetate solvent, and detected by Gas Chromatography-Mass Spectrometry (GCMS). Results: The recovery level of methadone analyte in the urine sample obtained was equal to 67% (N = 15) in QuEChERS method, and 49% (N =1 5) in LLE method. In this center, the LOD and LOQ of the methadone were determined, using GC-MS device, to be equal to 29.1ng/mL and 97ng/mL, respectively. According to the results obtained, there was a significant difference between QuEChERS and LLE methods, in terms of methadone test in post-mortem urine. Conclusion: Cheap, fast, effective, and green QuEChERS, improved with better recovery, could replace the LLE method in detecting methadone in Post-Mortem urine.