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Updated: Oct 12, 2025

Hollow Microneedle-based Sensor for Multiplexed Transdermal Electrochemical Sensing
Published on: June 1, 2012
Conformable microneedle pH sensors via the integration of two different siloxane polymers for mapping peripheral
Wonryung Lee1,2, Seung-Hwan Jeong3,4, Young-Woo Lim1
1Wearable Platform Materials Technology Center, Department of Materials Science and Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon 34141, Republic of Korea.
Abstract:
Flexible microneedles are important tools that allow access to the inside of biological tissue from the outside without surgery. However, it had been hard to realize microneedle sensor arrays on flexible substrates because of the difficulty of attaining a needle with a high Young’s modulus for a selected area on a thin or soft substrate. In this work, we developed a microneedle sensor on a hybrid substrate based on high Young’s modulus epoxy siloxane for the microneedles and low Young’s modulus polydimethylsiloxane for the conformable substrate. Polyaniline was deposited on the microneedle for pH sensing. The mechanical durability of the device was assessed by insertion into pig skin 1000 times. Last, the flexible microneedle pH sensors showed their utility for monitoring pH distribution in rats in a peripheral artery diseases model.

