Method for quantification of prazosin in dog plasma and its application to pharmacokinetic study

狗血浆中哌唑嗪的含量测定方法及其在药代动力学中的应用(英文)

A simple and sensitive high performance liquid chromatography method using fluorescence detection （HPLC- FLD） and a one-step single solvent extraction for the determination of prazosin（PZS） in dog plasma is developed and validated. After extraction with ether, the chromatographic separation of PZS is carried out using a reverse phase C18 column （ 150 mm ×4.6 mm, 5 μm） with a mobile phase of 30% acetonitrile and 70% acetic acid-sodium acetate buffer solution （pH = 3.6） and quantified by fluorescence detection operated with an excitation wavelength of 258 nm and an emission wavelength of 387 nm. The flow rate of the mobile phase is 1.0 mL/min and the retention time of PZS and the internal standard is found to be 4. 4 and 5. 8 rain, respectively. The calibration curve is linear within a concentration range from 1.0 to 1 000.0 ng/mL （ P 〉 0. 998）. The limit of detection is 0.4 ng/mL. The inter-day coefficient of variation （COV） of the calibration standards is below 5.0% and the mean accuracy is in the range from 92. 7% to 104. 2%. Moreover, by analyzing quality control plasma samples for three days, the results show that the method is precise and accurate, for the intra- and inter- day COV within 10% and the accuracy from 95.9% to 112.7%. The developed and validated method is successfully applied to phannacokinetic study for the preclinical evaluation of a new peroral PZS-sulfobutyl ether beta-cyclodextrin （PZS-SBE-β-CD） inclusion complex tablets （test preparation）, which demonstrates that the test preparation released PZS is conducted in a slow and controlled way, and the relative bioavailability of the test preparation is found to be 105.0%.

建立并评价了一种简单灵敏的方法测定狗血浆中PZS的含量.该方法利用HPLC-FLD结合乙醚萃取的前处理方法,采用C18色谱柱(150mm×4.6mm,5μm),流动相为30%乙腈和70%乙酸-乙酸钠缓冲液(pH=3.6),荧光检测器的激发波长为258nm,发射波长为387nm,在流动相流速为1.0mL/min时,其PZS和内标物的保留时间分别为4.4和5.8min.标准曲线在1.0～1000.0ng/mL的浓度范围内呈线性相关(r2>0.998),检出限为0.4ng/mL,标准曲线的日间变异系数低于5.0%,准确度在92.7%～104.2%范围内.在3d的分析质量控制研究中,日内和日间精密度均小于10%,准确度为95.9%～112.7%.该方法成功应用于一种新的口服制剂(PZS-磺丁基醚-β-环糊精包合物)的临床前期药代动力学评价,结果表明:该新型的包合药物具有缓释PZS的功效,且其相对生物利用率为105.0%.