AccScience Publishing / IJB / Volume 8 / Issue 1 / DOI: 10.18063/ijb.v8i1.447

Flexible, Wearable and Fully-printed Smart Patch for pH and Hydration Sensing in Wounds

Mick Iversen1 Monisha Monisha1 Shweta Agarwala1*
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1 Department of Electrical and Computer Engineering, Finlandsgade 22, Aarhus University, Aarhus, Denmark
Submitted: 30 September 2021 | Accepted: 15 November 2021 | Published: 16 December 2021
© 2021 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( )

Wound healing is a complex and dynamic regeneration process, wherein the physical and chemical parameters are continuously changing. Its management and monitoring can provide immense benefits, especially for bed-ridden patients. This work reports a low-cost, flexible, and fully printed on-skin patch sensor to measure the change in pH and fluid content in a wound. Such a bendable sensor can also be easily incorporated in a wound dressing. The sensor consists of different electrodes printed on polydimethylsiloxane (PDMS) substrate for pH and moisture sensing. The fabricated sensor patch has a sensitivity of 7.1 ohm/pH for wound pH levels. The hydration sensor results showed that moisture levels on a semi-porous surface can be quantified through resistance change.

Smart patch
Wound management
pH sensor
Hydration sensor
Flexible electronics
Printed electronics

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