Collaborative Research: IDBR: Development of a Biofluid Transport, Separation and Molecular Analysis System using Microfluidics and a Miniature Mass Spectrometer

生物系统通过产生独特的生化标志来应对环境压力和化学制剂，即生物标志物，当检测和正确解释时，这些生物标志物可以产生对有机体状态的巨大洞察。因此，这项工作的中心目标是开发一种集成的仪器，通过采集小体积流体样本，分离和预浓缩纳米流体-微流体芯片中的生物重要成分，然后在微型质谱仪中使用在线质谱仪对它们进行表征，来检测和识别生物标志物。在这一过程中，通过显著降低在复杂混合物中可以检测到特定有机分子的浓度水平，分子鉴定工具在生物学研究中的适用性将得到提高。将开发基于高频交流电喷雾电离和解吸电喷雾电离方法的转移和电离感兴趣化合物的新方案，并将其与传质效率、灵敏度和背景干扰等优值系数进行比较。一个特别的目标是提高电离步骤的效率，这是迄今为止质谱学中效率最低的过程。分析系统的关键性能测试将使用模拟脑脊液(CSF)的生物流体针对氧化应激的生物标记物。微/纳流体样品制备与微型大气压质谱仪的耦合为生物科学提供了许多价值，例如，使实现对基本代谢、调节和信号过程随环境因素的变化的实时功能分析成为可能。由于该项目的协同作用，质谱仪和微流控设备的性能将得到根本改善，使未来几代强大和实用的生物仪器成为可能。除了与生物学研究直接相关之外，成功的仪器开发还将影响医学诊断：与生物氧化过程相关的相同标记物与多种疾病的早期检测和预后密切相关，包括多发性硬化症、阿尔茨海默病、Niemann-Pick C、肌萎缩侧索硬化症、心脏病、帕金森病和缺血性中风，使结果易于翻译为人类健康研究。此外，培训高技能的仪器科学家是一种新兴的国家需求，这一需求将通过以下方式正式合作来满足：(1)圣母大学和普渡大学之间的研究型学生交流，以及(2)普渡大学分析仪器开发中心(CAID)和圣母大学高级诊断和治疗计划之间的更大规模的交流。这两个机构的目标是：(I)对仪器科学研究生进行培训；(Ii)从事仪器开发；(Iii)促进仪器的商业化；(Iv)通过仪器的商业化使区域经济受益。公众可以在相关网站上关注这些活动：http://sri.nd.edu/advanced-diagnostics-和-Treateutics/和www.Purdue.edu/dp/caid/。

Biological systems respond to environmental stresses and chemical agents by producing unique biochemical signatures, i.e. biomarkers, that - when detected and interpreted correctly - yield enormous insight into the state of the organism. Thus, the central objective of this work is to develop an integrated instrument that detects and identifies biomarkers by acquiring small- volume fluid samples, separating and pre-concentrating the biologically important components in a nanofluidic-microfluidic chip, and then characterizing them using on-line mass spectrometry in a miniature mass spectrometer. In the process, the applicability of molecular identification tools in biological research will be enhanced by significantly decreasing the concentration levels at which specific organic molecules can be detected in complex mixtures. Novel protocols for transferring and ionizing compounds of interest based on high-frequency ac electrospray ionization and desorption electrospray ionization methods will be developed and compared with respect to figures of merit, such as mass transfer efficiency, sensitivity and background interferences. One specific aim is to improve the efficiency of the ionization step, by far the least efficient process in mass spectrometry. Critical performance tests of the analysis system will target biomarkers for oxidative stress using biofluids which mimic cerebrospinal fluid (CSF). The coupling of micro/nano fluidic sample preparation to miniature atmospheric pressure mass spectrometers offers much value to the biological sciences, for example making it possible to realize real-time functional assays of changes in fundamental metabolic, regulatory and signaling processes in response to environmental factors. Fundamental improvements in the performance of mass spectrometers and in microfluidic devices will result from the synergy of this project, making possible future generations of biological instruments of great power and utility. In addition to the direct relevance to biological research, successful instrumentation development will impact medical diagnostics: The same markers relevant to biological oxidation processes are germane to the early detection and prognosis in a host of diseases, including multiple sclerosis, Alzheimer's disease, Niemann-Pick C, amyotrophic lateral sclerosis, heart disease, Parkinson's disease and ischemic stroke, making the results readily translatable to human health studies. Furthermore, the training of highly skilled instrumentation scientists is an emerging national need, and this need will be addressed by formalizing collaboration through (1) research student exchange between Notre Dame and Purdue and (2) larger scale exchanges between Purdue's Center for Analytical Instrumentation Development (CAID) and Notre Dame's Advanced Diagnostics and Therapeutics Initiative. Both institutions aim to (i) train graduate students in instrumentation science (ii) engage in instrumentation development, (iii) facilitate its commercialization, (iv) benefit the regional economy through instrument commercialization. The public can follow these activities at the relevant websites: http://sri.nd.edu/advanced-diagnostics- and-therapeutics/ and www.purdue.edu/dp/caid/.