利用毛細管電泳進行血漿中dl-methylphenidate之鏡像分析研究

Enantiomeric separation of dl-methylphenidate in human plasma by capillary electrophoresis

李詩潔(Shih-Chieh Lee)

指導教授 ： 吳秀梅

高雄醫學大學/藥學院/藥學研究所/碩士(2009年)

摘要

本論文建立一種分析派醋甲酯對掌異構物(dl-threo-methylphenidate)之毛細管電泳法，並實際應用於人體投藥後之血漿濃度測定。本法利用液相萃取法(萃取溶媒為正己烷)進行血漿樣品前處理後，於熔矽毛細管(全長41 cm，有效分析長度30 cm；內徑 50 μm) 通入分離用之磷酸鹽緩衝溶液( 50 mM，pH 3.00) 內含 30 mM triethanolamine 以及20 mM hydroxypropyl-β-cyclodextrin，以6 kV電壓取樣200秒，於20 kV電壓進行分離，以200 nm波長偵測之。方法經由確效後，其定量範圍為1 – 80 ng/mL，相關係數皆大於0.998，展現良好的線性關係；評估同日內及異日間分析的精確度及準確性，其RSD和RE皆小於5.5%，且偵測極限可達600 pg/ml (S/N=4，以6 kV電壓取樣200秒)。本分析方法亦成功應用於四位健康受試成年人，根據臨床投藥劑量(0.3 mg/kg) 給予藥物，由監測血中濃度經時變化，証實本方法之可行性，所得結果亦符合相關文獻中dl-MP藥物動力學之資料。目前正深入探討臨床應用，期待能提供臨床用藥劑量和使用頻率之評估及參考。

關鍵字

毛細管電泳 ； 鏡像分析

並列摘要

A simple and rapid capillary electrophoresis (CE) method was established for the chiral determination of dl-methylphenidate (dl-MP) in human plasma. This CE method was applied to analyze dl-MP to evaluate clinical efficiency. After liquid-liquid extraction with n-hexane, the sample was loaded by electrokinetic injection (6 kV, 200 s). The stacking step and separation were performed at 20 kV and detected at 200 nm using phosphate buffer (50 mM, pH 3.0) containing 30 mM triethanolamine and 20 mM hydroxypropyl-β-cyclodextrin. During method validation, calibration curves were linear (r≧ 0.998) over a range of 1 – 80 ng/ml. For the intra-day and inter-day precision and accuracy evaluation, the RSD and RE were all less than 5.5%. The limit of detection was 600 pg/ml(S/N=4, sampling 200 s at 6 kV). Our method had been further applied to investigate the pharmacokinetic study of four healthy volunteers by dosing dl-MP tablets according to their body weights (0.3 mg/kg). The results were coincident with reference data. Advanced applications in clinic are under investigation, we expect this study could provide more information for dl-MP administration.

並列關鍵字

dl-methylphenidate ； capillary electrophoresis ； enantiomeric separation

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