A portable, fast sensor for oxidative capacity of particulate air pollution

描述（由申请人提供）：该项目的目标是开发新的传感化学，以快速评估新收集的大气气溶胶在生物系统中引起氧化应激的能力。我们建议设计并验证一种新型氧化负荷传感器，该传感器将微流体的优点与一种新的气溶胶收集系统相结合。我们假设可以使用耦合到气溶胶颗粒收集器的微流体传感器来测量新收集的气溶胶颗粒的直接和间接氧化负荷。我们的方法是用紧凑、快速、廉价的微流体传感系统取代笨重、昂贵、缓慢的传统测量仪器（色谱/光谱学的过滤收集）。微流体提供了进行必要的化学反应，以确定氧化负荷的能力，而无需重复的手动步骤，并提供分析，以测量使用微升溶液体积产生的信号。这种溶液体积的减少可以大大减少采样和分析时间，同时仍然产生可测量的信号。微流体系统的小尺寸也将允许创建便携式传感器，具有个性化暴露评估的潜力。在我们测量这些气溶胶的反应性的同时，我们将使用在线气溶胶质谱法来提供关于氧化负荷与大气气溶胶的组成、大小和年龄之间关系的额外信息。该项目的目的是：具体目标1：设计，构建和测试一个微流体传感器耦合到一个颗粒收集器用于测量气溶胶氧化负荷。在这个以设计为中心的目标中，我们将创建用于测量直接和间接氧化负荷所需的新传感化学。我们还将在受控的实验室条件下评估检测和定量的分析限。具体目标2：测量新收集的大气气溶胶的直接和间接氧化负荷。在第二个目标中，我们将测试我们的中心假设，即测量新沉积的气溶胶颗粒的氧化负荷的能力。我们还将评估方法的敏感性和特异性方面使用替代，离线化学分析。

DESCRIPTION (provided by applicant): The goal of this project is to develop novel sensing chemistry to rapidly assess the ability of freshly collected atmospheric aerosols to cause oxidative stress in biological systems. We propose to design and validate of a novel sensor for oxidative load that combines advantageous aspects of microfluidics with a new aerosol collection system. We hypothesize that measurement of direct and indirect oxidative load from freshly collected aerosol particles can be achieved using a microfluidic sensor coupled to an aerosol particle collector. Our approach is to replace traditional measurement instrumentation (filter collection with chromatography/spectroscopy) that is bulky, expensive, and slow with sensing systems utilizing microfluidics that are compact, fast, and inexpensive. Microfluidics provides the ability to carry out the chemical reactions necessary to determine oxidative load without repeated manual steps and provide the analytics to measure the resulting signals using microliter solution volumes. This reduction in solution volume allows a dramatic reduction in sampling and analysis time while still generating a measurable signal. The small size of the microfluidic system will also allow a portable sensor to be created, with the potential for personalized exposure assessment. At the same time we measure the reactivity of these aerosols, we will use on-line aerosol mass spectrometry to provide additional information on the relationship between oxidative load and the composition, size, and age of atmospheric aerosol. The aims of this project are: Specific Aim 1: Design, build, and test a microfluidic sensor coupled to a particle collector for measurement of aerosol oxidative load. In this design-focused aim, we will create the new sensing chemistry required for measurement of direct and indirect oxidative load. We will also evaluate analytic limits of detection and quantification under controlled laboratory conditions. Specific Aim 2: Measure the direct and indirect oxidative loads of freshly collected atmospheric aerosols. In the second aim we will test our central hypothesis, the ability to measure oxidative load of freshly deposited aerosol particles. We will also evaluate aspects of method sensitivity and specificity using alternative, off-line chemical analyses. PUBLIC HEALTH RELEVANCE: An emerging hypothesis states that aerosols cause a majority of their harmful effects by eliciting cellular oxidative stress. Consequently, there is a need for advancement in the field of oxidative stress measurement related to environmental agents. A novel on-line monitoring tool that provides a more physiologically relevant measure of air pollution properties that correlate with human disease will support benchside, sub-clinical, nd population-level studies that seek to associate oxidative air pollution with human disease. Thus, this instrumentation will help researchers and policymakers better understand the sources and mechanisms by which air pollution induces adverse health outcomes in both healthy and at-risk populations.