Plasmonic Fluorescence Microarray Detection System

DESCRIPTION (provided by applicant): The long term objective of the proposed project I is to develop an affordable, highly parallel and highly sensitive detection system for protein and DMA chip applications. This system is based on a novel fluorescence detection technology with the potential for 10- to 1000-fold higher sensitivity than current state of- the-art fluorescence imaging systems. Importantly, the proposed technology will be implemented with relatively inexpensive CCD imaging instrumentation and with low-cost disposable chips. The principle behind the proposed enhancement in fluorescence detection sensitivity is a phenomenon known as surface plasmon coupled fluorescence (SPCF). The basis for the proposed technology rests on two key elements: a metal-coated, plastic sensor chip with periodic surface features that enable resonant coupling of optical radiation into surface plasmons, and surface chemistry with an interfacial architecture that enables positioning of the detection fluorescent dyes (e.g., fluorescent antibody conjugates) within 10-200nm of the metal surface. With this architecture and under appropriate excitations conditions, fluorescence emission is modified in two striking ways. First, the excitation field is enhanced, and second emission is highly directional, which can vastly improved optical collection efficiency. The specific aims of the Phase I are to 1) set up an experimental apparatus to test the proposed concept, 2) to fabricate chips with the appropriate interfacial architecture, and 3) to characterize the performance of the system. Expected future products (instrument and disposable chips) will be initially targeted to the analytical microchip market, the fastest growing technology segment in the life sciences today. The range of applications is very broad, covering fields as diverse as pharmaceutical development, food testing, clinical diagnostics, forensics, environmental analysis, bioprocess monitoring and biodefense.