Graphene quantum dots as smart probes for biosensing

In recent years, graphene quantum dots (GQDs) have attracted tremendous attention for their potential for biological, optoelectronic and energy-related applications, owing to their excellent biocompatibility, low cytotoxicity, stable photoluminescence (PL) and resistance to photobleaching. Among these applications, GQD-based biosensors are rapidly developed due to their particular PL, electrochemiluminescence (ECL) and electrochemical properties, which are highly sensitive to minute perturbations. In this review, recent exciting progress in GQD-based biosensors, such as PL sensors, ECL sensors and electrochemical sensors is highlighted. First, the synthesis and the fundamental properties of GQDs are briefly introduced. Then, emerged applications of PL, ECL and electrochemical biosensors are mainly addressed. Finally, their future potential developments are discussed and speculated.