Analysis of narcotic drugs in biological samples using hollow fiber liquid-phase microextraction and gas chromatography with nitrogen phosphorus detection

We report on a method for trace analysis of the narcotic drugs alfentanil, fentanyl, and sufentanil in plasma and urine. Two-phase hollow fiber liquid-phase microextraction was combined with GC using nitrogen-phosphorus detection. Experimental parameters were optimized to give a viable analytical procedure whose limits of detection range from 8 to 15 ng L-1 (at an S/N of 3). The calibration curves are linear between 0.1 and 50 mu g L-1, with squared correlation coefficients (r (2)) between 0.9953 and 0.9979. Precision values range from 2.4% to 3.3% (intra-day RSD) and 3.2 to 6.3% (inter-day RSD). The relative recoveries varied from 27.8% to 84.6% (for spiked plasma) and 75 to 85.2% (for spiked urine). The method consumes little solvent, is simple, fast, inexpensive, and well suitable for the analysis of complicated matrices.