SBIR Phase I: Hydrodynamically Driven Immunoassays: An Approach to Real Time Biosensing

This award is funded under the American Recovery and Reinvestment Act of 2009 (Public Law 111-5). This Small Business Innovation Research Phase I project addresses the need for a low cost technique to significantly minimize the time required to complete a diagnostic test while maintaining and possibly improving analytical and diagnostic sensitivity. The time required to complete an immunometric assay is often dictated by diffusion-based mass transport of antigen and label. Exacerbated by low diffusion coefficients inherent to proteins, viruses, and many other large disease markers, these and many other types of tests can take hours or days to complete. This Phase I proposal focuses on the development of an innovative hydrodynamic approach to increase reactant flux via a free liquid jet delivery system in a framework compatible with existing point-of-care (POC) and clinical instrumentation. The approach is predicated on the hypotheses that (1) mass transport is the rate-limiting step for most molecular recognition-based assays; and (2) the rate of nonspecific adsorption is slower than that of specific binding. This project explores the merits of using a spray jet technique as a means to enhance reactant flux, thereby markedly increasing assay speed while possibly lowering nonspecific adsorption. The broader impacts of this research are enabling the transition of diagnostics to the point of care. The increased focus on preventive healthcare is escalating the demand for rapid POC devices and high throughput clinical tests. The combined patient expectations from healthcare providers and the emergence of wellness testing sets the stage for new POC device genesis and platforms that can increase sample throughput for the in vitro diagnostics industry. Further magnifying the need for diagnostic technologies with as near to real time testing as possible are the needs to: (1) detect and contain the spread of infectious diseases in disaster relief responses; (2) monitor and counter threats to homeland security; (3) assure food and water quality; and (4) advance the health of underdeveloped countries. The ability to manipulate mass transport effects on immunometric and other assay platforms, and the commercial introduction of a hydrodynamic method to increase analyte and label flux, is projected to play a major role in defining assay speed in the next generation of diagnostic tests.