應用固相微萃取法分析苯二氮平類藥物

Abstract

本篇論文之目的在建立一項簡單、快速與靈敏度高的分析方法，用來篩檢生物檢體 (血漿及尿液)中之苯二氮平類 (benzodiazepine)藥物。苯二氮平類鎮靜安眠藥所須的劑量較早期使用的巴比妥類藥物少，其藥效發作的時間較短，且較少發生呼吸抑制作用，因此目前苯二氮平類藥物已大致取代了巴比妥類藥物成為臨床上的第一線用藥。 本研究首先探討四種不同披覆靜相纖維的萃取效果，發現Carboxen/ PDMS纖維具有最佳的萃取效果，並以此纖維進行後續研究，實驗結果顯示在酸鹼值5.5的飽和鹽類溶液下，以60℃進行90分鐘的萃取，可以得到最佳萃取效果，結合氣相層析儀/電子捕捉偵測器分析苯二氮平類藥物，在ppb濃度層級仍有良好的再現性，檢量線最低濃度時訊號峰面積的相對標準偏差皆小於7.54 %，分析物滯留時間的相對標準偏差則都小於0.45%，偵測極限最低可達0.30 ppb。 分析尿液及血漿樣品時，尿液樣品中分析物之萃取回收率介於21.86 %與79.35% 之間；血漿樣品中分析物之萃取回收率則在10.86 %到62.19 %之間。推測造成分析物萃取回收率偏低的原因，以尿液樣品而言可能為分析物會與尿液中之葡萄糖甘酸結合，以致於萃取纖維上的披覆靜相需要和葡萄糖甘酸互相競爭目標分析物；而血漿樣品則是除了基質本身的影響外，在除去血漿蛋白質的過程中，可能有部份分析物仍然吸附在已沉澱的血漿蛋白質上，因而造成分析物的流失。

Benzodiazepines are one of the most popular prescribed drugs and commonly used for hypnotics, minor tranquillisers, anticonvulsants and muscle relaxants of clinical medicines. In this study, a simple and sensitive method of solid-phase microextraction (SPME) coupled with gas chromatography/electron capture detector (GC/ECD) for screening benzodiazepines in aqueous solution, plasma, and urine was developed. Also, several important factors determining direct SPME efficiency were studied. The Carboxen/PDMS fiber was chosen by its highest extraction amounts than the other fibers including 85-µm PA, 65-µ-m Carbowax/DVB, and 65--µm PDMS/DVB fibers. The optimum extraction condition was under pH 5.5 with saturated salt and sampling for 90 minutes at 60oC with agitation. The method shows good reproduction for determination of benzodiazepines at ppb levels. The reproducibility of retention times is excellent with less than 0.45% of the coefficients of variation. The limits of detection in aqueous solution were from 0.30 to 178 ng/mL. The plasma sample pretreatment was sufficient to protect fiber from complex matrix. The extraction recoveries of all thirteen benzodiazepines from urine and plasma were higher than 21.86% and 10.86% respectively.