Application of Functionalized Ag Nanoparticles for the Determination of Proteins at Nanogram Levels Using the Resonance Light Scattering Method

Abstract

A novel method for the determination of proteins in aqueous solutions has been developed based on the enhancement of resonance light scattering (RLS) of Ag nanoparticles in the presence of proteins. Factors including acidity of the media, concentration of Ag hydrosol, reaction time, temperature, and interference of non-protein substances were investigated. Under the optimal conditions, with the enhanced RLS signals at 452 nm, the linear ranges of calibration curves were 0–0.8 µg mL−1 for bovine serum albumin (BSA), 0–1.2 µg mL−1 for human serum albumin (HSA), and 0–2.5 µg mL−1 for human γ-IgG (γ-IgG), respectively. The detection limits were 1.3 ng mL−1 for BSA, 10 ng mL−1 for HAS, and 5.7 ng mL−1 for γ-IgG.