FÖrster resonance energy transfer (FRET)-based biosensors for biological applications.

FÖrster resonance energy transfer (FRET)-based biosensors have achieved great success for biological applications. However, what is not extensively appreciated is the growing role as versatile FRET biosensors within a similar biological context. This review provides a brief introduction of recent advances in principle, the designing strategies and kinds of applications of FRET biosensors. For each FRET biosensor, the appropriate background and fabrication is explained before studying their related applications. The prominent roles of nanomaterials are present in the development of more sensitive and specific FRET biosensors. Finally, the challenges and outlooks of FRET biosensors are emphasized.