[Separation and determination of morphine, pethidine and diazepam by high performance liquid chromatography]

Morphine, penthidine and diazepam in blood were determined by high performance liquid chromatography (HPLC). The HPLC system was consisted of 10 microns particle size C18 column and UV detector set at 254 nm. The mobile phase was V(CH3OH):V(25 mmol/L KH2PO4) = 90:10 with a flow rate of 1.0 mL/min. The average recoveries of morphine, penthidine and diazepam were 93.27%, 90.23% and 93.29% respectively. The linear range was between 0.05-50 mg/L. The detection limit was 0.05 mg/L and CV was less than 6%.