A Visual Sensor Array for Pattern Recognition Analysis of Proteins Using Novel Blue-Emitting Fluorescent Gold Nanoclusters

This paper describes a visual sensor array for pattern recognition analysis of proteins based on two different optical signal changes: colorimetric and fluorometric, by using two types of novel blue-emitting collagen protected gold nanoclusters and macerozyme R-10 protected gold nanoclusters with lower synthetic demands. Eight proteins have been well-discriminated by this visual sensor array, and protein mixtures after one-dimensional polyacrylamide gel electrophoresis also could be well-discriminated. The possible mechanism of this sensor array was illustrated and validated by fluorescence spectra, X-ray photoelectron spectroscopy (XPS), fluorescence lifetime, isothermal titration calorimetry (ITC), and matrix-assisted laser desorption/ionizationtime-of-flight mass spectrometry (MALDI-TOF MS) experiments. It was attributed to that the adsorption of proteins onto the surface of gold nanoclusters (Au NCs), forming the proteinAu NCs complex. Furthermore, serums from normal and hepatoma patients were also effectively discriminated by this visual sensor array, showing feasible potential for diagnostic applications.