Yeung P K, Jamieson A, Smith G J, Fice D, Pollak P T
Pharmacokinetics and Metabolism Laboratory, College of Pharmacy, Faculty of Health Professions, Dalhousie University, Halifax, NS, Canada.
Int J Pharm. 2000 Aug 25;204(1-2):17-22. doi: 10.1016/s0378-5173(00)00453-1.
To establish a HPLC assay for plasma losartan and its active metabolite EXP3174 to facilitate clinical pharmacokinetic studies.
the HPLC system consisted of a 250 x 2 mm i.d. C18 reversed phase column preceded by a 4 x 4 mm guard column, a UV detector set at 254 nm, and an integrator. The mobile phase was a mixture of 0.01 M ammonium phosphate: acetonitrile: methanol (6:3:1) containing 0.02 % sodium azide and 0.04% TEA, with pH adjusted to 3.2. The system was operated isocratically at ambient temperature at a flow rate of 0.3 ml/min. Losartan and its active metabolite EXP3174 were extracted from plasma using C2 bonded silica gel standard solid phase extraction.
recoveries of losartan and EXP3174 from plasma were greater than 70%. Using 0.5 ml of plasma sample, standard curves were linear from 10 to 300 ng/ml (r2 = 0.996 and 0.997 for losartan and EXP 3174, respectively). Sensitivity of the assay was < 10 ng/ml. Intra-and inter-assay variations were < 10 and 15%. respectively. The assay has been successfully applied to measuring plasma concentrations of losartan and EXP3174 in patients receiving a daily dose of losartan (50-100 mg).
The HPLC assay has adequate sensitivity, reproducibility, and specificity for clinical pharmacokinetic studies.
建立一种用于测定血浆中氯沙坦及其活性代谢产物EXP3174的高效液相色谱法，以促进临床药代动力学研究。
高效液相色谱系统由一根内径为250×2mm的C18反相柱和一根4×4mm的保护柱组成，配备一个设定在254nm的紫外检测器和一个积分仪。流动相为含有0.02%叠氮化钠和0.04%三乙胺的0.01M磷酸铵：乙腈：甲醇（6:3:1）混合物，pH值调至3.2。该系统在室温下等度运行，流速为0.3ml/min。氯沙坦及其活性代谢产物EXP3174采用C2键合硅胶标准固相萃取法从血浆中提取。
氯沙坦和EXP3174从血浆中的回收率大于70%。使用0.5ml血浆样品，标准曲线在10至300ng/ml范围内呈线性（氯沙坦和EXP3174的r2分别为0.996和0.997）。该测定法的灵敏度<10ng/ml。批内和批间变异分别<10%和15%。该测定法已成功应用于测定每日服用氯沙坦（50 - 100mg）患者血浆中氯沙坦和EXP3174的浓度。
该高效液相色谱法对临床药代动力学研究具有足够的灵敏度、重现性和特异性。
