SBIR Phase I: Active Titanium Dioxide Nanoprobes as Biosensors for Detection and Diagnostics

This Small Business Innovation Research (SBIR) Phase I project will develop a biosensor to detect proteins or biomacromolecules (viruses, spores, etc.) in real time with increased specificity and decreased background compared with the current state-of-the-art. Currently, biosensors rely on solid-state, colorimetric or fluorescence assays that require expensive equipment for result evaluation. In this proposal, the technology is based on a biologically-active, photoexcitable nanoprobe that will trigger the activation of a reporter enzyme upon binding to the target of interest. In this Phase I project, two biosensors -- a surface sensor and a solution sensor -- will be developed based on the same bioconjugated nanoprobe (BNP) platform. These BNP sensor systems improve on the design of the sandwich immunoassay by utilizing multi-layered detection specificity towards the target of interest. The reporter signal is released only when multiple binding molecules are engaged concurrently, but is prevented from release if only one or none of the binding molecules are engaged. This design allows for differentiation between different isoforms or species of the target molecule as well as decreases background noise in the sensor. A sensor with these attributes would re-define the state-of-the-art for sensor and detection technology. In this Phase I project active bioconjugated nanoprobes will be developed into both surface and solution sensors. The surface sensor could be used as a local or remote detection device, with numeric results appearing on an LCD screen or sent back to a monitoring site, respectively. The solution sensor could be used instead of an ELISA assay thereby alleviating the need for a platereader, as the results could be interrogated with a spectrophotometer or simply as a ""yes"" or ""no"" visual result. Commercially, these biosensors would represent significant advances in detection of chemical and biological warfare and improvised explosive device agents, as their design increases the level of stringency, allows detection in real time as binding occurs, reports results without specialized detection equipment, and allows remote interrogation. The sensor design would differentiate between type of agents and decipher a mixture of agents reliably, eventually using a subdivided platform on a chip to achieve detection and differentiation of multiple targets simultaneously. The biosensor platform presented in this proposal represents a major advance in detection technology. This research should result in desirable commercial products in areas as diverse as the Department of Defense, Homeland Security, the biotechnology and pharmaceutical industries, and academia.