Flexible and mountable microfluidics for wearable biosensors

Microfluidics is a well-consolidated multidisciplinary technology with the capability of precise control and manipulation of fluids at the micron-scale. This unique feature endows microfluidic-based devices with several merits compared to conventional laboratory-based macroscale techniques. These merits include much smaller sample sizes and reagent volume requirements, high-throughput, low-cost, high-resolution separations and sensitivity, enabling numerous opportunities in various biomedical applications such as organ-on-a-chip, cell biology, material fabrication, drug delivery, and micro-total analysis systems. In recent years, microfluidics has been playing a vital role as one of the key components, integrated with electronics and optical transducers, in the fabrication of biomedical analytical devices such as biosensors for sample collection and handling, as well as for signal transduction and amplification. On the other hand, flexibility and portability have gained significant interest in the field of device fabrication, particularly in wearable sensors and biosensors to track an individual’s physiological information in decentralized locations at a physical fitness level or for medical treatment. The advancement in flexible materials and wearable electronics in recent years has driven the development of the next generation of flexible and wearable devices that can be intimately attached to human skin and tissue externally or implanted internally to deliver accurate, continuous, and remote measurement of physiological parameters or biomarkers. This also brings new opportunities in the field of flexible and mountable microfluidics, migrating from conventional rigid to emerging flexible materials for high body compliance, further serving as an excellent sample–device interface in wearable sensors and biosensors.