Abstract
The growing demand for non-invasive, real-time health monitoring has driven the development of graphene-based wearable biosensors for point-of-care (POC) diagnostics. This review explores the surface functionalization of graphene and its critical role in enhancing the performance of wearable biosensors for biomarker detection. Leveraging graphene's exceptional electrical, mechanical, and biocompatible properties, we discuss how surface functionalization-such as covalent and non-covalent functionalization, biomolecular probes, and passivation layers-enable highly sensitive and selective detection of biomarkers in biofluids. We categorize biomarkers based on their physical properties and explore various wearable designs, including patches, contact lenses, microneedles, and textiles, highlighting their integration into POC devices. Furthermore, we examine the challenges and opportunities in translating graphene-based sensors from the lab to real-world applications, emphasizing the importance of biocompatibility and surface functionalization for improved performance. By bridging the gap between material science and biomedical engineering, this review provides a roadmap for the development of next-generation graphene biosensors that could revolutionize personalized medicine and point-of-care diagnostics.