[Lab on a chip] Directly embroidered micro-tubings for fluid transport in wearable applications
We demonstrate, for the first time, a facile and low-cost approach for integrating highly flexible and stretchable microfluidic channels into textile-based substrates. The integration of the microfluidics is accomplished by means of directly embroidering surface-functionalized micro-tubing in a zigzag/meander pattern and subsequently coating it with an elastomer for irreversible bonding. We show the utility of the embroidered micro-tubing by developing robust and stretchable drug-delivery and electronic devices. Controlled drug-delivery platforms with sustained release are achieved through selected laser ablated openings. We further demonstrate a wearable wireless resonant displacement sensor capable of detecting strains ranging from 0 to 60% with an average sensitivity of 45 kHz/%strain by filling the embroidered tubing with liquid metal alloy, creating stretchable conductive microfluidics with < 0.4 Ω resistance variations at their maximum stretchability (100%). The interconnects can withstand 1500 repeated stretch-and-release cycles at 30% strain with less 0.1 Ω change in resistance.
Rahim Rahimi, Wuyang Yu, Manuel Ochoa and Babak Ziaie Lab Chip, 2017, Accepted Manuscript DOI: 10.1039/C7LC00074J Received 19 Jan 2017, Accepted 22 Mar 2017 First published online 24 Mar 2017