SBIR Phase I: Surface Enhanced Raman Scattering Tags for Multiplexed Analysis

This Small Business Innovation Research (SBIR) Phase I project aims to develop Surface Enhanced Raman Scattering (SERS) nanotags for diagnostic and security applications. A novel class of SERS tags that exhibit much higher performance than other tag formulations were demonstrated. This novel class of tags consists of a bimetallic nanoparticle with the Raman-active molecule trapped at the metal/metal junction. In this project, four spectrally distinct SERS tags will be fabricated, coated with silica shells, and functionalized with antibodies to provide specific targeting for diagnostic applications, or with polymers to provide stability in solvents and inks for security applications. Tags will be characterized using a novel high throughput flow spectroscopy instrument capable of analyzing thousands of individual SERS tags, enabling rapid optimization of tag formulations. The performance of optimized tags will be tested in diagnostic and security applications to demonstrate and quantify tag efficacy. The broader/commercial impact of this project will be the potential to provide bright, robust, and spectrally distinct molecules and nanoparticles that can be used to identify and track biologics, people, and products. Currently fluorescent molecules are the most commonly used tag; however, due to their spectral widths, current instrumentation is limited to tracking only 5-20 tags simultaneously. SERS tags, with their very narrow spectral features thus more distinct variants, offer the promise of much higher multiplexing.