Instrumental Innovations for Membrane Introduction Mass Spectrometry

分析化学的最终目标是鉴定和测量现实世界样品中的痕量分子水平。不幸的是，在复杂的实际样品（城市废水、血液、尿液、组织液等）中进行的痕量水平测量可能会被样品的其他主要成分（干扰物）混淆，从而对成功的结果产生不利影响。直接测定是可取的，因为它们简单，并且可以减少由于污染或稀释而改变结果的风险。在实际样品（农药、激素、药物、代谢物等）中成功测量环境和人类健康的关键决定因素具有挑战性，因为许多当前的分析需要样品清理、浓缩和其他准备步骤，增加了时间和成本，以及潜在污染或稀释样品的风险。***我的研究项目旨在开发新方法，用于直接，在线，“实时”测量复杂，真实样品中的痕量水平分子（分析物），在环境，生物分析（医学，制药）和材料科学中具有重要应用。这项工作的基础是使用聚合物（或其他）膜作为复杂的空气或水基样品和质谱仪（MS）之间的直接桥梁，用于后续痕量分析物的鉴定和测量。该技术被称为膜导入质谱（MIMS），是直接和连续的，消除了样品预处理步骤：定量的，分子特异性的测量是可能的。从样品转移到膜上的分析物以混合物的形式转移，在那里它们被转化为离子，并由质谱仪进行分析。因为样品的分析物在膜上的转移是连续的，所以MIMS还可以确定浓度随时间的变化，提供在分析单个样品时可能错过的关键信息（例如实时空气质量测量、工业废物流监测、即时医疗诊断等）。***MIMS对分析物的选择性源于膜的选择、离子生成方法和质量测量步骤。我的研究将探索改进的、小型化的膜样品接口的发展，实现对小样本的快速、低成本、选择性、直接测量，研究选择性和敏感的离子产生方法及其后续的质谱检测，以及紧凑、便携式基于MIMS的系统的进化发展，从长远来看，这些系统将在需要的时间和地点实现直接、实时的测量，提供实验室外的高精度结果。在重大事件（环境泄漏）等事件以及提供及时的医疗诊断、提高保健质量、改善所有加拿大人的生活质量方面至关重要。

The identification and measurement of trace levels of molecules in real world samples is the end goal of analytical chemistry. Unfortunately, trace level measurements made in complicated, real-world samples (municipal waste water, blood, urine, tissue fluids, etc.) can be confounded by the other, major components of the samples (interferents), adversely affecting successful results. Direct determinations are desirable, because they are simple, and can reduce the risk of altering the results through contamination or dilution. The successful measurement of key determinants of environmental and human health in real samples (pesticides, hormones, drugs, metabolites, etc.) is challenging because many current analyses require sample cleanup, concentration and other preparation steps, adding both time and cost, as well as the risk of potential contamination or dilution of the samples.***My research program is aimed at developing new approaches for the direct, online, ‘real-time' measurement of trace level molecules (analytes) in complex, real samples, with important applications in environmental, bioanalytical (medical, pharmaceutical) and material sciences. The basis for this work is to use polymer (or other) membranes as a direct bridge between complex air or water based samples and mass spectrometers (MS), which are used for the subsequent identification and measurement of trace level analytes. The technique, called membrane introduction mass spectrometry (MIMS), is direct and continuous, eliminating sample pretreatment steps: quantitative, molecularly specific measurements are possible. Analytes that transfer from the sample across the membrane do so as a mixture, where they are converted into ions, and analyzed by the MS. Because analyte transfer from a sample is continuous across the membrane, MIMS can also determine concentration changes over time, providing key information (e.g. real-time air quality measurements, industrial waste stream monitoring, point-of-care medical diagnostics, etc.) that can be missed when analyzing single samples. ***MIMS' selectivity for analytes arises from the membrane choice, the ion generation approach and the mass measurement steps. My research will explore the development of improved, miniaturized membrane-sample interfaces, enabling rapid, low-cost, selective, direct measurements for small samples, investigate selective and sensitive ion generation approaches and their subsequent MS detection, and the evolutionary development of compact, portable MIMS based systems, that in the long term will enable direct, real-time measurements when and where they are needed, providing high precision results out-of-the-lab, crucial in events such as critical incidents (environmental spills) as well as in providing timely medical diagnostics, enabling better quality health care, improving the quality of life for all Canadians.