Low-cost electrospun nanofibers for label-free and real-time optical biodetection purposes

In the development of label-free and real-time optical biosensors, a straightforward and low-cost fabrication of the transducer is important, because it reduces costs and the complexity of the process. One possibility for such easy fabrication is electrospinning. It is a versatile and well-developed technique that allows the manufacturing of layers of nanofibers at a low cost with a Fabry-Perot cavity-based optical response when illuminated with visible light. In this research, the suitability of such layers for the development of label-free and real-time optical biosensors is studied. For such aim, the nanofibers were biofunctionalized in flow with antibodies against bovine serum albumin through an intermediate layer of protein A/G. Then, BSA was flowed at a concentration of 10 µg/ml as the target analyte. As a result, biofunctionalization and biodetection processes were optically monitored in real-time successfully, demonstrating the suitability of such a simple-to-fabricate transducer for the development of label-free and real-time optical biosensors. Furthermore, in comparison with other optical transducers that require complex nanofabrication techniques, electrospun nanofibers can be deposited over vast areas to create several transducers in a single batch and at a low cost.