Design principle in biosensing: Critical analysis based on graphitic carbon nitride (G-C₃N₄) photoelectrochemical biosensor

Photoelectrochemical (PEC) biosensing has been attracting increasing attention as the generation of PEC current resulting from the biological interactions between biorecognition element and analyte has rendered PEC biosensor with high sensitivity and low detection limit. This review provides a panoramic snapshot of this dynamically developing field, with special emphasis on the design principle in biosensing, critically analyzing graphitic carbon nitride (g–C₃N₄)–based PEC biosensor. The basis and synthesis approaches for g-C₃N₄ are summarized, detailing the recent work done. This review highlights the novel concept of g–C₃N₄–based PEC biosensor based on three design principles: turn-on, turn-off and ratiometric, providing comprehensive design guidelines for researchers to develop more advanced PEC biosensors. Finally, future outlook and challenges for the progression of PEC biosensor are also evaluated and discussed. This work will serve as a useful and informative source for interested audience regarding the latest developments of g–C₃N₄–based biosensor in the field of PEC bioanalysis.