Colloidal Gold as Molecular Capture Devices in Hybrid Nano/microfluidic Systems for Mass-Limited Sample Analysis

Abstract

Analyte capture by the colloidal gold was demonstrated in a hybrid nano/microfluidic device designed for sequential fluid manipulations in three dimensions. A nanocapillary array membrane (NCAM) was utilized to enable efficient mixing of the gold colloid and the adsorbate in-device. Fluorescence microscopy was used to monitor fluorescence quenching during monolayer self-assembly of analytes on the colloidal gold surface. The kinetics of the heterogeneous reaction was fit using a second order reversible kinetics model and the adsorption rate constant was compared to reported values for thiols on planar gold substrates.