高效液相色谱法测定人血浆中莫西沙星浓度

目的：建立以高效液相色谱法测定人血浆中莫西沙星浓度的方法。方法：以Kromasil C8柱为固定相，0．05mol·L^-1磷酸二氢钾缓冲液：甲醇：乙腈（65：15：20）为流动相，调节pH至3．0，流速1ml·min^-1，柱温30℃，紫外检测波长296nm，进样量20ul。沉淀剂选用8％高氯酸溶液，以峰面积外标法定量。结果：莫西沙星保留时间为6．2min，线性范围0．08—4．80mg·L^-1，最低定量限为0．08mg·L^-1；方法平均回收率为95．20％～100．85％，绝对回收率为79．98％～91．83％；高、中、低系列浓度日内RSD为4．69％-5．23％，日间RSD为6．08％～7．36％；样品在低温冷冻条件下至少可稳定保存28d。结论：本法简便、快速，灵敏度高，重复性好，适用于临床血药浓度测定及药动学研究。

Determination of Moxifloxaxin Concentration in Plasma by HPLC

Objective： To establish an HPLC method for determination of moxifloxacin concentration in human plasma and to study its pharmacokinetics. Method： The separation was performed on a Kromasil C8 column with mobile phase consisted of 65% 0.05mol. L^-1 potassiun dihydrogen phosphorate buffer solution （containing 1% triethylamine, pH adjusted to 3.0）, 15% methanol and 20% acetonitrile. The flow rate was 1.0 ml.min^-1 and the detection wavelength was at 296 nm. The column temperature was 30℃ and injection volume was 20ul. 8% perchloric acid was chosen as precipitator. External standard method was used. Result： The retention time of moxifloxacin was about 6.2 min. The calibration curve was linear within the concentration range of 0.08 - 4.80 mg·L^-1. The limit of quantitation （LOQ） was 0.08 mg·L^-1. The recovery of methodology was 95.20% - 100.85% ; and the absolute recovery was 79.98% - 91.83%. RSD for within day precision and between day precision were 4.69% - 5.23% and 6.08% - 7.36% %, respectively. The sample under frozen condition was stable at least within 28 days. Conclusion： The established HPLC method is simple, sensitive and accurate. It could be used for the determination of moxiflocacin concentration in plasma and its pharmacokinetics study.