Emerging functional materials for microfluidic biosensors

The integration of microfluidic technology together with biosensors is an attractive choice for the fabrication of miniaturized components in a single device and opens new opportunities for future biosensing applications, including portability, ease of use, and high-throughput analysis. Pairing microfluidic devices with biosensors has lead to the development of a wide range of new functional features for improving biosensing performance. Various conventional materials such as silicon, glass, ceramic, polydimethylsiloxane, and paper are the most common materials used in microfluidic biosensors; meanwhile, advancements in polymer material science have driven the emerging three-dimensional-printed microfluidics to enable facile design and fabrication of complexed microfluidic architectures coupled with sensing components for novel microfluidic biosensors with new features. On the other hand, advanced materials have also contributed to the improvement of signal transduction in microfluidic biosensors. In particular, graphene-based two-dimensional (2D) nanomaterials, 2D transition metal nanomaterials (such as transition metal oxides, transition metal dichalcogenides), MXenes, and black phosphorus were used for the development of high-performance electrochemical transducers in microfluidic biosensors. Here, we discuss and summarize various advanced functional materials for the fabrication of microfluidic platforms for biosensing, as well as the use of nanomaterials to improve signal transduction in microfluidic biosensors.