ABSTRACT
OBJECTIVE:To establish a method for the content determination of zolpidem tartrate in microsamples of rat plas-ma. METHODS:Rats were given zolpidem tartrate solution 3 mg/kg intragastrically,and 0.2 ml blood sample were collected and isolated. 50 μl plasma was precipitated by methanol,and the supernatant was determined by HPLC-fluorescence combined with ex-ternal method. Agilent HC-C18 column was used with mobile phase consisted of 0.03 mol/L KH2PO4 solution(containing 0.2% tri-ethylamine)-methanol (33∶67,V/V) at flow rate of 1.0 ml/min. The excitation and emission wavelengths were 254 nm and 390 nm,respectively. The sample size was 20 μl. RESULTS:The linear ranges of zolpidem tartrate in plasma was 2-200 μg/L(r=0.999 7),and the limit of quantification was 2 μg/L. The method recoveries of zolpidem were (96.96 ± 1.35)%-(105.0 ± 5.36)%(RSD=2.20%-4.88%,n=5),and extraction recoveries were (79.72 ± 0.01)%-(80.77 ± 0.02)%(RSD=1.34%-3.90%,n=5). The intra-day and inter-day RSDs were 1.40%-5.10% and 3.22%-9.25%(n=5),respectively. CONCLUSIONS:The method is simple,sensitive and suitable for the content determination of zolpidem tartrate in microsamples of plasma.