Development of a Reliable, Low-Cost and User-Friendly Spot Test Kit for Leaded Dust Based on Recent Advances in Bionanotechnology

Lead in household paint and dust is a serious health hazard, as low-level lead exposure can result in a number of adverse health effects, especially in children. Onsite and real-time detection and quantification of lead in paint/dust are very important to homeowners and certified lead-based paint removal professionals. Toward this end, both field-portable equipment (such as X-ray fluorescence instruments and anodic stripping voltammetry) and colorimetric spot test kits (based on sulfide or rhodizonate ion) have been used. Although the portable instruments generally are reliable, their relatively high costs and use of sophisticated parts (such as the radioactive X-ray sources) make them difficult for homeowners and some professionals to use on a routine basis. On the other hand, although spot tests provide low-cost and user-friendly alternatives, the U.S. Environmental Protection Agency (EPA) and U.S. Department of Housing and Urban Development (HUD) studies show that their reliability is inadequate. DzymeTech, Inc., proposes to develop a reliable spot test kit that is based on patented and patent-pending technologies developed by Dr. Yi Lu’s group at the University of Illinois, Urbana-Champaign (UIUC). The technology employs catalytic DNA for lead detection. Under SBIR Phase I funding from EPA, DzymeTech has demonstrated the feasibility of using the catalytic DNA-based detection approach for lead in dust in terms of sensitivity, selectivity, interference, precision, stability, and long-term storage. In Phase II, we propose to build and test a prototype of the lead sensor. The prototype kit will contain all the sensor reagent and components with minimal manual transfer of solution needed. The prototype kit will be characterized in terms of sensitivity, selectivity and stability, and will be tested by different users (including EPA inspectors and home-owners) for field sample assays. To achieve the objective of developing a reliable, low-cost, and user-friendly spot test kit, DzymeTech will investigate methods for efficient dust sample collection, lead extraction, and applications of the colorimetric lead sensors under different conditions. Both simulated and real lead dust samples will be used for the test kit evaluation. Factors that improve user-friendliness, shelf-life, and cost-effectiveness of the test kit will be evaluated.