Liquid metal based flexible microfluidic device for wireless sensor applications

Liquid metal enabled wearable technology provides a promising for flexible electronics. This paper reports a Galinstan based flexible microfluidic device for wireless applications. The microchannel is made on the PDMS substrate and the Galinstan as a conductive material is injected into the microfluidic channel to form the sensor circuit. The microfluidic device uses capacitive sensing principle for measuring the physical quantity and inductive coupling-based readout method for wireless communication of data and power. The flexibility of the device is characterized by fixing it on the human body and can be applied in the remote areas to accomplish wireless sensing platform. The device demonstration displays exceptional electrical stability under high human motions like wrist flexion, hand movement and finger bending without any fall in performance during mechanical degradation. We believe our microfluidic device provides a benchmark for flexible wearable electronics in wireless and remote sensing applications.