Report the design, fabrication, and characterization of novel biochemical sensors consisting of nanoscale grooves and slits milled in a metal film to form two-arm, three-beam, planar plasmonic interferometers. By integrating thousands of plasmonic interferometers per square millimeter with a microfluidic system, we demonstrate a sensor able to detect physiological concentrations of glucose in water over a broad wavelength range (400–800 nm). A wavelength sensitivity between 370 and 630 nm/RIU (RIU, refractive index units), a relative intensity change between 103 and 106 %/RIU, and a resolution of 3 × 10–7 in refractive index change were experimentally measured using typical sensing volumes as low as 20 fL. These results show that multispectral plasmonic interferometry is a promising approach for the development of high-throughput, real-time, and extremely compact biochemical sensors.
Nanoscale Plasmonic Interferometers for Multispectral, High-Throughput Biochemical Sensing
Jing Feng, Vince S. Siu, Alec Roelke, Vihang Mehta, Steve Y. Rhieu, G. Tayhas R. Palmore, and Domenico Pacifici
Nano Letters 2012 12 (2), 602-609 [on line] http://pubs.acs.org/doi/abs/10.1021/nl203325s