Metallic nanoparticle-based glassy carbon electrodes for smart biosensing

Glassy carbon electrodes (GCEs) remain a cornerstone in electrochemical biosensing due to their conductivity, stability, and reliability for surface modifications. Incorporation of metallic nanoparticles (MNPs) onto GCEs has significantly improved biosensor performance, particularly in terms of sensitivity, selectivity, and signal transduction. Despite extensive applications using noble and transition metal nanostructures, a systematic understanding of how MNP characteristics such as morphology, composition, and deposition methods impact biosensing across enzymatic, immunological, and nucleic acid platforms remains underexplored. This review critically examines recent advances in MNP-GCE systems, emphasizing nanomaterial design, surface functionalization strategies, and incorporating emerging smart biosensing trends. It discusses the integration of artificial intelligence (AI), machine learning (ML), and Internet of Things (IoT) technologies for next-generation smart sensing applications. Key challenges such as reproducibility, real-sample compatibility, and commercial scalability are highlighted, along with future directions for advancing robust, intelligent biosensors for point-of-care and digital healthcare applications.