Colorimetric sensor array based on gold nanoparticles: Design principles and recent advances

A sensor array based on the pattern recognition strategy is good at distinguishing subtle changes of extremely similar mixtures over a wide range of analyte types. Particularly, colorimetric sensor arrays based on gold nanoparticles (AuNPs) have been applied widely in many fields for its simplicity, rapidity, cost-effective production, multi-information output, easy visualization of the color change, and even assay by naked eyes. This comprehensive review focuses on the development and state of the art of AuNPs-based colorimetric sensor arrays. Firstly, this review briefly describes the principle of a sensor array and discusses the design of the cross-reactive sensing elements. Secondly, the popular chemometric and statistical techniques (including hierarchical cluster analysis (HCA), principal component analysis (PCA), and linear discriminant analysis (LDA)) for analyzing the data from a sensor array have also been presented. Thirdly, a variety of applications of AuNPs-based colorimetric sensor arrays published throughout the literature have been reviewed in detail according to different sensing mechanisms (surface plasmon resonance, catalytic activity of mimetic enzyme, and multidimensional information) between AuNPs and target analytes. Finally, the remaining challenges and future trends in the development of colorimetric sensor array based on AuNPs have also been discussed.