Disposable pipette extraction for the simultaneous determination of biperiden and three antipsychotic drugs in human urine by GC–nitrogen phosphorus detection

Disposable pipette extraction with reversed-phase sorbent is proposed for the fast and simple GC determination of the antipsychotic drugs chlorpromazine, olanzapine, clozapine and biperiden – an anticholinergic drug – in human urine. The method was validated and successfully applied to postmortem urine samples. The analytical run was 11 min and lidocaine was used as the internal standard. Results: The developed method showed good linearity, over the range of 0.34 to 5 ng/µl, for all compounds. The within-day and between-day precision and accuracy assays revealed values ≤15%, while the recoveries ranged from 85 to 120%. LOD and LOQ ranged from 0.28...