Gold nanoparticle-based optical nanosensors for food and health safety monitoring: recent advances and future perspectives

Modern society has been facing serious health-related problems including food safety, diseases and illness. Hence, it is urgent to develop analysis methods for the detection and control of food contaminants, disease biomarkers and pathogens. As the traditional instrumental methods have several disadvantages, including being time consuming, and having high cost and laborious procedures, optical nanosensors have emerged as promising alternative or complementary approaches to those traditional ones. With the advantages of simple preparation, high surface-to-volume ratio, excellent biocompatibility, and especially, unique optical properties, gold nanoparticles (AuNPs) have been demonstrated as excellent transducers for optical sensing systems. Herein, we provide an overview of the synthesis of AuNPs and their excellent optical properties that are ideal for the development of optical nanosensors based on local surface plasmon resonance (LSPR), colorimetry, fluorescence resonance energy transfer (FRET), and surface-enhanced Raman scattering (SERS) phenomena. We also review the sensing strategies and their mechanisms, as well as summarizing the recent advances in the monitoring of food contaminants, disease biomarkers and pathogens using developed AuNP-based optical nanosensors in the past seven years (2015-now). Furthermore, trends and challenges in the application of these nanosensors in the determination of those analytes are discussed to suggest possible directions for future developments.

Automated summary

Modern society is facing serious health problems, such as food safety, diseases and illness. Therefore, it is urgent to develop analysis methods for the detection and control of food contaminants, disease biomarkers, and pathogens. Gold nanoparticles (AuNPs) have emerged as promising transducers for optical sensing systems due to their simple preparation, high surface-to-volume ratio, excellent biocompatibility, and unique optical properties. This review provides an overview of the synthesis of AuNPs and their optical properties, as well as the recent advances in the development of AuNP-based optical nanosensors for monitoring food contaminants, disease biomarkers, and pathogens. The challenges and future directions in the application of these nanosensors are also discussed.