Nanofibers interfaces for biosensing: Design and applications

Biosensors are analytical tools that can be used as simple, real-time and effective devices in clinical diagnosis, food analysis, and environmental monitoring. In the last years, electrospun nanofiber's engineering has emerged as a possible strategy to improve the performance of biosensor devices. These nanostructures present a high surface-to-volume ratio, interconnected porous structure, low barrier to diffusion, and adjustable surface functionality. Additionally, nanofibers have also been demonstrated to work efficiently as platforms to immobilize biomolecules, providing a suitable microenvironment to biologically active molecules, which is beneficial for biosensing performance. This review aims to highlight the different strategies (e.g., adsorption, covalent binding, entrapment, and imprinting) for immobilizing functional receptors onto nanofibers surface for the development of specific and sensitive (bio)chemical assays, which can be used for a wide range of applications. The attractive features of electrospun nanofibers and the biorecognition elements properties are also presented and discussed. Finally, the current challenges and future opportunities for the design of nanofiber-based biosensing interfaces are also addressed.