ABSTRSCT:

A portable and quantitative enzyme immunoassay with glucometer readout was developed for sensitive monitoring of neuron-specific enolase (NSE, as a model analyte) in a high-binding polystyrene 96-well microtiter plate (MTP), conjugated with monoclonal mouse anti-human NSE antibody (mAb1). Gold nanoparticle heavily functionalized with glucoamylase and polyclonal rabbit anti-human NSE antibody (pAb2) was utilized as the trace tag. A sandwich-type immunoassay format was adopted for quantitative detection of NSE in mAb1-functionalized MTP. Accompanying the gold nanoparticle, the carried glucoamylase could hydrolyze amylopectin in glucose. The produced glucose could be quantitatively monitored using a portable personal glucose meter (PGM). Under optimal conditions, the PGM-based immunoassay exhibited good analytical properties for the determination of the target NSE, and allowed detection of NSE at concentrations as low as 0.05 ng mL-1. Intra- and interassay coefficients of variation (CVs) were below 10% and 11%, respectively. The methodology was also evaluated by assaying 15 clinical serum samples, and showed good accordance between results obtained by the developed immunoassay and the referenced values.