The goal of the proposed research is to develop a platform technology for simultaneous detection of multiple analytes with better efficiency and lower cost. Currently, immunoassays are extensively used in biomedical research, clinical diagnostics, food/water safety testing, and biological warfare defense. Although they can be performed in a microplate (e.g. 96 wells) to increase sample throughput, the immunoassay in each well is generally limited to one analyte per test. Such a format is inefficient and not cost-effective for the requirement to detect multiple analytes in a sample. For instance, a spectrum of toxic agents should be simultaneously monitored in foods and drinking water. Similarly, a set of biomarkers, rather than an individual biomarker, should be detected for a particular disease to enhance the accuracy. Therefore, a platform to detect multiple analytes simultaneously is desirable for better efficiency and lower cost. <P> The specific aims of the proposed research are to (1) design and optimize an array of microfluidic valves that are required for containing reagents, directing and regulating flows; (2) demonstrate the microfluidics-enabled multiplexed immunoassay array in the format of sandwich assays and study the effects of surface modification, flow rate, reagent concentration on the assay; and (3) validate the immunoassay array by detecting multiple analytes including toxins and biomarkers. <P> The significance of the research lies in the following aspects. First, the proposed research will lead to a platform for simultaneous detection of multiple analytes. Such a capability will lead to efficient and cost- effective methods. Secondly, the microfluidic-enabled immunoassay array will have shorter analysis time and a reduction in the consumption of required sample and reagents. These advantages could have a significant impact since immunoassays are widely used in chemical, biological and clinical laboratories. Thirdly, the proposed research will result in a manufacturable process that allows mass production of low-cost, disposable devices. <P> The ability to be disposable after a single use could have a tremendous impact to applications where cross-contamination of sequential samples is of concern.
Public Health Relevance: A platform technology capable of simultaneous detection of multiple analytes in one test can be used for simultaneously detecting of a wide range of toxic agents; such a capability is essential when US is facing with the potential threats of terrorism. It can also be exploited for screening a number of biomarkers associated with a disease; such a capability will lead to efficient and cost-effective medical diagnostics.