Microwave-Accelerated Plasmonics: Application to Ultra-Fast and Ultra-Sensitive Clinical Assays

In recent years our laboratory has described the favorable effects of fluorophores in close proximity to metallic nanostructures (1-6). These include, increased system quantum yields (increased detectability) and much improved fluorophore photostabilities. These effects have led to many applications of metal-enhanced fluorescence (MEF) including, improved DNA detection (7, 8), enhanced ratiometric sensing (5), metal-enhanced phosphorescence (9) and chemiluminescence signatures (10), as well as to the development of nano-rod (6), triangular nano-plate (4) and modified plastic surfaces (1, 3) for their multifarious applications. In all of our applications of MEF to date, we have been able to significantly optically amplify luminescence based signatures, but have been unable to modify the rates of the respective biochemical reactions being either studied or utilized, as these are dependent on the usual solution parameters of temperature, viscosity and their bioaffinity etc. However, our laboratory has recently shown that low power microwaves, when applied to the metallic nanostructures which are suitable for MEF, are preferentially heated, rapidly accelerating local biochemical reactions (11). Subsequently, ultra-fast and ultra-sensitive assays can be realized. We have recently termed the amalgamation of both MEF with microwave heating as “Microwave-Accelerated Metal-Enhanced Fluorescence (MAMEF)”. In this conference proceeding, we summarize our MAMEF work on ultra-fast and sensitive myoglobin detection for rapid cardiac risk assessment and DNA detection for bioterrorism applications. In addition we present two new platform technologies, namely, Microwave-Accelerated Surface Plasmon-Coupled Directional Luminescence (MA-SPCL) for ultra fast assays using clinical samples and a Microwave-Accelerated Aggregation Assay (MA-AA) technology, for ultra fast solutionbased nanoparticle aggregation assays.