Department of Chemistry, University of Victoria, Victoria, British Columbia, Canada.
Rapid Commun Mass Spectrom. 2013 Jun 15;27(11):1213-21. doi: 10.1002/rcm.6560.
High-throughput, automated analytical measurements are desirable in many analytical scenarios, as are rapid sample pre-screening techniques to identify 'positive' samples for subsequent measurements using more time-consuming conventional methodologies (e.g., liquid chromatography/mass spectrometry (LC/MS)). A miniature condensed-phase membrane introduction mass spectrometry (CP-MIMS) probe for the direct and continuous, on-line measurement of pharmaceuticals and environmental contaminants in small, complex samples is presented.
A miniature polydimethylsiloxane hollow fibre membrane (PDMS-HFM) probe is coupled with an electrospray ionization (ESI) triple quadrupole mass spectrometer. Analytes are transported from the probe to the ESI source by a methanol acceptor phase. The probe can be autosampler mounted and directly inserted in small samples (≥400 μL) allowing continuous and simultaneous pptr-ppb level detection of target analytes (chlorophenols, triclosan, gemfibrozil, nonylphenol) in complex samples (artificial urine, beer, natural water, waste water, plant tissue).
The probe has been characterized and optimized for acceptor phase flow rate, sample mixing and probe washing. Signal response times, detection limits and calibration data are given for selected ion monitoring (SIM) and tandem mass spectrometry (MS/MS) measurements of target analytes at trace levels. Comparisons with flow cell type CP-MIMS systems are given. Analyte depletion effects are evaluated for small samples (≥400 μL). On-line measurements in small volumes of complex samples, temporally resolved reaction monitoring and in situ/in vivo demonstrations are presented.
The miniature CP-MIMS probe developed was successfully used for the direct, on-line detection of target analytes in small volumes (40 mL to 400 μL) of complex samples at pptr to low ppb levels. The probe can be readily automated as well as deployed for in situ/in vivo monitoring, including reaction monitoring, small sample measurements and direct insertion in living plant tissue.
在许多分析情况下，高通量、自动化的分析测量是理想的，并且需要快速的样品预筛选技术来识别“阳性”样品，以便随后使用更耗时的传统方法学（例如液相色谱/质谱法（LC/MS））进行测量。本文介绍了一种用于直接和连续在线测量小而复杂样品中药物和环境污染物的微型凝聚相膜导入质谱（CP-MIMS）探头。
采用微型聚二甲基硅氧烷中空纤维膜（PDMS-HFM）探头与电喷雾电离（ESI）三重四极杆质谱仪联用。分析物通过甲醇接受相从探头输送到 ESI 源。该探头可安装在自动进样器上，并直接插入小样品（≥400μL）中，从而能够连续同时检测目标分析物（氯酚、三氯生、吉非罗齐、壬基酚）在复杂样品（人工尿液、啤酒、天然水、废水、植物组织）中的ppb 级水平。
该探头已针对接受相流速、样品混合和探头清洗进行了特征化和优化。给出了选定离子监测（SIM）和串联质谱（MS/MS）测量痕量目标分析物的信号响应时间、检测限和校准数据。与流动池式 CP-MIMS 系统进行了比较。评估了小样品（≥400μL）中的分析物消耗效应。本文还介绍了小体积复杂样品中的在线测量、时间分辨反应监测以及原位/体内演示。
所开发的微型 CP-MIMS 探头成功用于直接在线检测小体积（40mL 至 400μL）复杂样品中的目标分析物，达到 ppt 至低 ppb 水平。该探头易于自动化，也可用于原位/体内监测，包括反应监测、小样品测量以及直接插入活体植物组织。
