Development of a Microfluidic Paper Analytical Device (uPAD) for Airborne Metals

描述(由申请人提供)：这项研究的主要目标是开发新技术，以确定个人在工作场所接触空气中金属的特征。第二个目标是改进空气中金属暴露评估的灵敏度和时间分辨率的最新水平。这项工作的关键是一种名为微流控纸分析设备(5PAD)的创新技术，它以低成本、高灵敏度的形式将采样和分析相结合。我们的中心假设是，5PADs可以集成到个人气溶胶采样器中，用于量化个人对空气中金属的暴露，采样和分析时间不到一小时。为了验证这一假设，我们提出了以下具体目标：(1)构建与现有尺寸选择性个人气溶胶采样器兼容的用于金属分析的单分析物微流控纸张分析装置(5PAD)；(2)构建用于空气中铅、铜、锰和镍浓度分析的多分析物5PAD；(3)验证多分析物5PAD的现场性能。上述目标的成功实现将为工业卫生员提供一种灵敏的现场技术，以评估工作场所空气中的金属危险。这种技术代表着暴露评估领域的一种范式转变，因为它有可能用灵敏度和时间分辨率更高的直接现场分析技术取代样品运送和实验室分析的传统做法(这两种做法都是时间和资源密集型的)。这项研究通过开发一种新的、廉价的仪器(跨行业主题)来评估工人接触空气中金属(影响到交通/公用事业、制造业和建筑业)(一个跨行业主题)，从而为国家职业研究议程(NORA)做出了贡献。5PAD样品的化学分析预计至少比传统的电感耦合等离子体质谱或原子发射光谱技术的分析成本低一个数量级(每个样品约5美元)。此外，将5PAD集成到现有的气溶胶采样设备(即可吸入过滤器采样器)中，将通过执业职业健康专业人员来提高其接受度。这项技术可能会打开气溶胶暴露评估的新领域的大门，因为5PAD可以被改装成检测和量化许多金属、有机或无机化合物。 公共卫生相关性：暴露评估的主要目的是确定和预防可能导致伤害和疾病的工作场所条件。暴露评估方法依赖于对健康危害进行定量测量的能力，几乎不确定或没有不确定性，这是工作场所许多新出现的呼吸危害(例如，铍、镉和工程纳米颗粒)所缺乏的假设。这里提出的抽样技术(5PAD)将有助于减少这种不确定性，因为它为工业卫生员提供了足够低的检测限值，足以做出关于保护工人健康的知情决定，并通过在不增加暴露评估成本的情况下帮助职业流行病学家检测呼吸系统疾病。

DESCRIPTION (provided by applicant): The primary objective of this research is to develop new technology to characterize personal exposure to airborne metals in the workplace. The secondary objective is to improve upon the state-of-the-art in both sensitivity and time-resolution of airborne metals exposure assessment. Key to this effort is an innovative technology called microfluidic paper analytical devices (5PADs) that integrate sampling with analysis in a low cost, high sensitivity format. Our central hypothesis is that 5PADs can be integrated into personal aerosol samplers for quantification of personal exposure to airborne metals with sampling and analysis times of less than one hour. To test this hypothesis, we propose the following specific aims: (1) Construct a single-analyte microfluidic paper analytical device (5PAD) for metal analysis that is compatible with existing, size-selective personal aerosol samplers; (2) Construct a multi-analyte 5PAD for analysis of Pb, Cu, Mn, and Ni concentrations in air; (3) Validate the performance of the multi-analyte 5PAD in the field. Successful completion of the above aims will provide industrial hygienists with a sensitive, in-situ technique to assess airborne metal hazards in the workplace. Such technology represents a paradigm shift in the field of exposure assessment, as it has the potential to replace the traditional practice of sample shipment and laboratory analysis (both of which are time and resource intensive) with a direct, field analysis technique with improved sensitivity and time-resolution. This research contributes to the National Occupational Research Agenda (NORA) by developing a new and inexpensive instrumentation (a cross-sector theme) for assessing worker exposure (a cross-sector theme) to airborne metals (affecting the transportation/utilities, manufacturing, and construction sectors). Chemical analysis of a 5PAD sample is expected to be at least an order of magnitude less expensive (around 5$ per sample) than analysis with traditional ICP-MS or AES techniques. Furthermore, integrating the 5PAD into existing aerosol sampling devices (i.e., inhalable filter samplers) will enhance its acceptance by practicing occupational health professionals. This technology may open the door to a new realm of aerosol exposure assessment, as 5PADs can be adapted to detect and quantify many metal, organic, or inorganic compounds. PUBLIC HEALTH RELEVANCE: The primary purpose of exposure assessment is to identify and prevent workplace conditions likely to cause injury and disease. Exposure assessment methods rely on the ability to make quantitative measurements of health hazards with little or no uncertainty, an assumption that is lacking for many emerging respiratory hazards in the workplace (e.g., beryllium, cadmium, and engineered nanoparticles). The sampling technology proposed here (5PAD) will help reduce this uncertainty by providing industrial hygienists with detection limits low enough to make informed decisions on protecting worker health and by aiding occupational epidemiologists in the detection of respiratory diseases without a proportionate increase in exposure assessment costs.