Gold nanomaterials-derived colorimetric signaling strategies for immunosensing and food safety

Background

The food industry faces significant challenges from spoilage and contamination, leading to frequent food safety incidents and substantial economic losses. As a result, the development of sensors capable of detecting foodborne contaminants has become increasingly critical.

Scope and approach

Colorimetric immunosensors are particularly favored for their specificity, cost-effectiveness, portability, and ease of signal interpretation. Gold nanomaterials (AuNMs) are widely employed in colorimetric immunosensors owing to their superior optical properties, affinity, and catalytic activity, which enable accurate and reliable detection. However, achieving accurate and reliable detection remains a significant challenge for traditional colloidal gold. To address this issue, researchers have proposed various effective improvement strategies while preserving the inherent advantages of AuNMs. This study investigates both intrinsic and activated colorimetric immunosensing methods based on AuNMs, with an emphasis on their application in food safety monitoring. Specifically, this review first categorizes and summarizes signal strategies derived directly from the nanolabels themselves, followed by a detailed introduction of catalytic reactions.

Key findings and conclusions

This review offers valuable insights into enhancing current colorimetric detection methods and establishes a solid foundation for the development of diversified “colorimetric + other signals" immunoassays. Furthermore, it addresses the challenges encountered in AuNMs-based colorimetric immunoassays and outlines future development directions, providing a novel approach to designing sensing modes tailored to the specific needs of the food industry.