目的建立HPLC手性固定相法检查左旋奥硝唑(S-奥硝唑)中对映异构体杂质(R-奥硝唑)。方法用Chiralpak IC为手性固定相,正己烷-异丙醇(体积比为85∶15)为流动相,流速为1.0mL·min-1,柱温为27℃,检测波长为310 nm。结果R-奥硝唑在质量浓度为0.10~0.35mg·L-1内线性良好(r=0.999 3),方法回收率为95.9%~102.9%(RSD=2.5,n=9)。结论建立的方法可用于左旋奥硝唑中R-异构体杂质的检查。 OBJECTIVE To establish an HPLC method for the determination of enantiomeric impurities (R-ornidazole) in levonoridazole (S-ornidazole) by HPLC. Methods Chiralpak IC was used as the chiral stationary phase. The mobile phase was n-hexane-isopropanol (volume ratio 85:15). The flow rate was 1.0 mL · min-1. The column temperature was 27 ℃ and the detection wavelength was 310 nm. Results The calibration curve of R-ornidazole was linear in the range of 0.10-0.35 mg · L-1 (r = 0.999 3). The recoveries ranged from 95.9% to 102.9% (RSD = 2.5, n = 9). Conclusion The established method can be used for the detection of R-isomer impurities in levorotary ornidazole.