Fluorescence resonance energy transfer-based nanomaterials for the sensing in biological systems

The applications of fluorescence resonance energy transfer (FRET) are coming to be one of the simplest and most accessible strategy with super-resolved optical measurements. Meanwhile, nanomaterials have become ideal for constructing FRET-based system, due to their unique advantages of tunable emission, broad absorption, and long fluorescence (FL) lifetime. The limitations of traditional FRET-based detections, such as the intrinsic FL, auto-FL, as well as the short FL lifetime, could be overcome with nanomaterials. Consequently, numbers of FRET-based nanomaterials have been constructed for precise, sensitive and selective detections in biological systems. They could act as both energy donors and/or acceptors in the optical energy transfer process for biological detections. Some other nanomaterials would not participate in the energy transfer process, but act as the excellent matrix for modifications. The review will be roughly classified into nanomaterial-involved and uninvolved ones. Different detection targets, such as nucleic acids, pathogenic microorganisms, proteins, heavy metal ions, and other applications will be reviewed. Finally, the other biological applications, including environmental evaluation and mechanism studies would also be summarized.