Au–Ag bimetallic nanoparticles: Synthesis, structure, and application in sensing

Abstract

Biosensors are crucial for detecting various analytes relevant to bioanalytical applications. To enhance the specificity and sensitivity of biosensors, bimetallic nanoparticles (BNPs) have been utilized, which demonstrate significant potential for sensing applications owing to their constituent materials’ inherent properties, small size, unique architectural features, and biomimetic behavior. Among BNPs, Au–Ag BNPs are promising for sensing applications owing to their small size, high sensitivity, and distinctive characteristics. Herein, we first briefly present the development of Au–Ag BNPs and discuss the fundamentals. Subsequently, we present the relationship between the synthesis method and structure of Au–Ag BNPs. Furthermore, recent advancements in Au–Ag BNPs are highlighted for their role in enhancing biosensors, particularly for electrode modifiers, signal amplifiers, and recognition materials. Finally, we propose several existing challenges and summarize insights pertaining to the potential development of Au–Ag BNPs for biosensing applications.

Keywords

Au–Ag bimetallic nanoparticles / Biosensing / Electrochemistry / Synthesis

Declaration of Competing Interest

The authors declare the following personal relationships which may be considered as competing interests: Prakash Somani is currently employed by Applied Science Innovations Pvt. Ltd. Other authors declare that there are no competing interests.

CRediT authorship contribution statement

Ajinkya Nene: Writing – review & editing, Writing – original draft. Ganesha Antarnusa: Writing – review & editing, Writing – original draft. Kanika Dulta: Investigation, Formal analysis. Sorour Sadeghzade: Methodology. Liwen Wang: Methodology. Chandan Hunsur Ravikumar: Visualization. Junaid Aman: Visualization. Banlambhabok Khongthaw: Visualization. Abhishek Kandwal: Writing – review & editing, Investigation. Prakash Somani: Supervision. Ashish Kumar: Data curation. Krishnamoorthy Ramachandran: Data curation. Vadivel Subramaniam: Data curation. Massimiliano Galluzzi: Writing – review & editing, Supervision. Shixue Dou: Supervision. Xinghui Liu: Validation, Writing – review & editing, Writing – original draft.

Acknowledgements

This study was supported by the Hubei Province Technology Innovation Program Project (2024BCB073), the National Natural Science Foundation of China (grant no. 32071318, T2350610283), the Shenzhen Science and Technology Innovation Committee (grant no. JCYJ20190807163007525), and the Youth Innovation Promotion Association of the Chinese Academy of Sciences (grant no. 2022363). All authors are grateful for the support from the King Mongkut’s University of Technology Thonburi, Bangkok, Thailand. The authors thank Professor Mithran Somasundrum for his support and valuable suggestions.

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