利用液相層析串聯質譜儀搭配離子遷移光譜術分析尿液中之苯二氮類藥物

Abstract

本研究利用液相層析串聯質譜儀(Ultra-performance liquid chromatography; UPLC-MS/MS)搭配離子遷移光譜術(Differential Ion Mobility Spectrometry; DMS) 開發一快速、高選擇性以及高靈敏度的方法分析人類尿液中之濫用藥物及其代謝物。DMS最重要的功能為可以提高選擇性以及改善訊噪比(signal-to-noise ratio)，以實現定量樣品中的微量分析物。在DMS中，高分離電壓 (SV) 與有機溶劑之修飾劑 (例如，異丙醇、乙腈及其混合物) 將加入DMS的漂移氣體裡。苯二氮類藥物之半衰期較快，是一種常見的醫療鎮靜安眠劑，但是，在刑事案件上常發現被用來降低被害者的知覺能力，使其喪失意志，而對被害者進行身體或財物的侵害。在苯二氮類藥物裡，alprazolam為常見的濫用藥物之一。Alprazolam的半衰期是大約12到15小時左右。使用與分析物相關的補償電壓（Compensation voltage; CoV），以選擇性DMS離子通過質量分析器，找出利用液相層析串聯質譜儀與搭配離子遷移光譜術，可檢測尿液中微量之殘留代謝產物，可以測定吃藥後6天在尿液樣品中之alprazolam和它代謝物α-hydroxyalprazolam的含量。再現性分為intra-day, inter-day (n=3) 皆少於14％，線性範圍為0.1-100 ng mL-1，線性回歸係數R2 ≧0.998。本方法延展一般鎮靜安眠藥在尿液中的檢出時間(12-48小時)，至藥物使用後之6天，有利於釐清此類藥物在醫療上或犯罪上之使用角色。

The present work describes a rapid, selective and sensitive approach coupling ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and modifier-assisted differential ion mobility (DMS) spectrometry mass spectrometry to investigate drugs of abuse and their metabolites in urine. The most important feature of DMS is the increase the selectivity and improving the signal-to-noise ratio to achieve lower limits of detection in the range of sample. In DMS the combination of a high separation voltage (SV) together with organic modifier (e.g., IPA, ACN) added in the drift gas. An analyte-dependent compensation voltage (CoV) was applied to selective ions through the DMS cell to the mass analyzer. Benzodiazepines are selected as the analytes, which are common sedative hypnotic agents. Recently they have been found to reduce the defensing ability of assault victims in crime. Using our investigated method, alprazolam and its metabolites, α-hydroxyl-alprazolam was identified in real urine samples after administration of alprazolam for 5-6 days. We here showed the development of a sensitive technique and looked for stable metabolites to detect in urine compounds of interest at trace level. The linear range of the method was 0.1 to 100 ng mL-1 for all benzodiazepines, linear plots yielded R2 ≧ 0.998. And the limits of detection (LODs) ranged from 0.1 to 1 ng mL-1 , the residual standard deviation (RSD) ranged from 2~14%.