DESCRIPTION (provided by applicant): The main goal of the project is to increase the sensitivity of microtransponder-based multiplexed bioassays by (1) introducing a coating with silver nanostructures onto the microtransponders (MTPs) to enhance fluorescence emission, and (2) improving the sensitivity of fluorescence detection of the analyzer. The key element of the assay is the MTP, a monolithic 500 W 500 <m integrated circuit chip that can transmit its identification code at a radio frequency (RF). Each chip consists of photocells, read-only memory (ROM), transmit logic circuitry, and an integrated antenna which, when illuminated, transmit an ID through a varying magnetic field. In an assay, the chips are derivatized with a molecular probe capable of binding to an analyte of interest that can be fluorescently labeled. The chips are read in a high speed, fluidic\-based analyzer. The analyzer decodes the MTP ID and measures the fluorescence intensity on the surface to index and report information about molecular interactions in the assay. Increased metal-enhanced fluorescence is a phenomenon based on light-induced plasmon formation in the metal, often silver, and transmission of this energy through fluorescence. During the course of the project, we will coat MTPs with different types of sliver nanostructures, quantitate and characterize fluorescence enhancement on the surface of the MTP. In addition, the analyzer will be improved to measure very low fluorescence levels. One of the goals of the project is to develop a protein-based, multiplex assay to detect urine biomarkers for prostate cancer (PCa). The selected biomarkers are AMACR (a racemase), endoglin, annexin A3 and cytokine IL-6. The biomarkers were chosen because of their unique expression profile in PCa patient samples versus those in healthy controls. The multiplex MTP assay involves the following steps: (a) conjugation of capture antibodies to silver nanostructure coated microtransponders, (b) deposition of the targeted antigen specimen source, (c) detection using the corresponding number of biotinylated antibodies and a reagent for visualization. We will design and develop the assay, as well as standardize the assay performance against the biomarker controls. Assay procedures will be optimized using individual ELISA antigen-antibody assays configured & optimized before an MTP biomarker assay is performed. In order to analyze the data from the analyzer, we will modify existing hardware and software.
PUBLIC HEALTH RELEVANCE: The proposed system for an ultra-sensitive assay provides a new tool for performing several tests at once. The system is applicable to cancer diagnostics and other medical ailments providing a more powerful, simpler to use and less costly approach. An assay will be developed to diagnose prostate cancer by testing urine in an non-invasive way at early phases of the disease. The assay has a potential to also improve PCa disease management. Acceptance of nanotechnology-based multiplex assays on microtransponders by researchers and clinicians could initiate new methods in disease diagnosis and treatment, drug discovery, and biological or environmental research.