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 of development and equipping of forensic centers to new diagnostic devices .
Objectives: In present study, a comparison was conducted between extraction of methadone in post-mortem urine using modified QuEChERS method and conventional liquid-liquid extraction method (LLE) in forensic medicine .
Method: QuEChERS extraction was a simple and fast tube method using MgSO4 and NaCl salts And ethyl acetate solvent and detection by GC-MS .
Result: The recovery level of methadone analyte of urine sample was obtained equal to 67% (N=15) in QuEChers method and equal to 49% (N=15) in LLE method. In this center, LOD and LOQ of methadone was determined using GC-MS device equal to 29.1ng/mL and 97ng/mL, respectively. According to the obtained results, there was significant difference between QuEChERS and LLE methods in the term 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.