Hanpitakpong Warunee, Banmairuroi Vick, Kamanikom Benjamas, Choemung Anurak, Na-Bangchang Kesara
Faculty of Allied Health Sciences, Pharmacology and Toxicology Unit, Thammasat University (Rangsit Campus), Paholyothin Road, Pathumthani 12121, Thailand.
J Pharm Biomed Anal. 2004 Nov 19;36(4):871-6. doi: 10.1016/j.jpba.2004.07.043.
A simple, sensitive, selective and reproducible method based on a reversed-phase chromatography was developed for the determination of praziquantel in human plasma. Praziquantel was separated from the internal standard (diazepam) on a Luna C18 column (250 mm x 4.6mm, 5 microm particle size), with retention times of 4.8 and 6.2 min, respectively. Ultraviolet detection was set at 21 7 nm. The mobile phase consisted of acetonitrile and distilled water (70:30, v/v), running through the column at a flow rate of 1.0 ml/min. The chromatographic analysis was operated at 25 degrees C. Sample preparation (1 ml plasma) was done by a single step liquid-liquid extraction with the mixture of methyl-tert-butylether and dichloromethane at the ratio of 2:1 (v/v). Calibration curves in plasma at the concentrations 0, 50, 100, 200, 400, 800 and 1600 ng/ml were all linear with correlation coefficients better than 0.999. The precision of the method based on within-day repeatability and reproducibility (day-to-day variation) was below 15% (relative standard deviation: R.S.D.). Good accuracy was observed for both the intra-day or inter-day assays, as indicated by the minimal deviation of mean values found with measured samples from that of the theoretical values (below +/-15%). Limit of quantification (LOQ) was accepted as 5 ng using 1 ml samples. The mean recovery for praziquantel and the internal standard were greater than 90% for both praziquantel and internal standard. The method was free from interference from the commonly used antibiotic and antiparasitic drugs. The method appears to be robust and has been applied to a pharmacokinetic study of praziquantel in three healthy Thai volunteers following a single oral dose of 40 mg/kg body weight praziquantel.
建立了一种基于反相色谱法的简单、灵敏、选择性好且可重复的人血浆中吡喹酮测定方法。吡喹酮在Luna C18柱（250 mm×4.6mm，5μm粒径）上与内标（地西泮）分离，保留时间分别为4.8分钟和6.2分钟。紫外检测波长设定为217nm。流动相由乙腈和蒸馏水（70:30，v/v）组成，以1.0 ml/min的流速流经色谱柱。色谱分析在25℃下进行。样品制备（1 ml血浆）采用一步液-液萃取法，用甲基叔丁基醚和二氯甲烷按2:1（v/v）的比例混合。血浆中浓度为0、50、100、200、400、800和1600 ng/ml的校准曲线均呈线性，相关系数优于0.999。基于日内重复性和重现性（日间变化）的方法精密度低于15%（相对标准偏差：R.S.D.）。日内和日间测定均具有良好的准确性，实测样品的平均值与理论值的偏差最小（低于±15%）。使用1 ml样品时，定量限（LOQ）为5 ng。吡喹酮和内标的平均回收率均大于90%。该方法不受常用抗生素和抗寄生虫药物的干扰。该方法似乎很可靠，已应用于三名健康泰国志愿者单次口服40 mg/kg体重吡喹酮后的吡喹酮药代动力学研究。
