Optical flexible biosensors: From detection principles to biomedical applications

Optical flexible biosensors are novel sensors fabricated on flexible or ductile materials that are used for the detection of analytes. Compared to traditional sensors, these biosensors offer greater flexibility, which allows them to adapt to different working environments, to meet the deformation requirements of humans. Flexible devices can not only detect alterations in analytes in vitro, but can also realize real-time and non-invasive monitoring of the variation of physical conditions or metabolites in vivo. Flexible devices are earning increasing attention from researchers and clinicians. In the present review, we summarize and introduce the detection principles, key analytes, and applications of optical flexible biosensors in the diagnosis/treatment of diseases as well as health detection. Moreover, the remaining challenges of flexible devices and their perspectives have also been addressed. We hope that this review will pave ways for the development of more feasible and multifunctional flexible devices.