A Hydrogel-Based Ultrasonic Backscattering Wireless Biochemical Sensing

Juhong Nam; Eunjeong Byun; Hyunji Shim; Esther Kim; Sayemul Islam; Moonchul Park; Albert Kim; Seung Hyun Song

doi:10.3389/fbioe.2020.596370

A Hydrogel-Based Ultrasonic Backscattering Wireless Biochemical Sensing

Front Bioeng Biotechnol. 2020 Nov 27:8:596370. doi: 10.3389/fbioe.2020.596370. eCollection 2020.

Authors

Juhong Nam¹, Eunjeong Byun¹, Hyunji Shim¹, Esther Kim¹, Sayemul Islam², Moonchul Park², Albert Kim², Seung Hyun Song¹

Affiliations

¹ Department of Electronics Engineering, Sookmyung Women's University, Seoul, South Korea.
² Department of Electrical and Computer Engineering, Temple University, Philadelphia, PA, United States.

Abstract

Wireless monitoring of the physio-biochemical information is becoming increasingly important for healthcare. In this work, we present a proof-of-concept hydrogel-based wireless biochemical sensing scheme utilizing ultrasound. The sensing system utilizes silica-nanoparticle embedded hydrogel deposited on a thin glass substrate, which presents two prominent interfaces for ultrasonic backscattering (tissue/glass and hydrogel/glass). To overcome the effect of the varying acoustic properties of the intervening biological tissues between the sensor and the external transducer, we implemented a differential mode of ultrasonic back-scattering. Here, we demonstrate a wireless pH measurement with a resolution of 0.2 pH level change and a wireless sensing range around 10 cm in a water tank.

Keywords: biochemical sensing; hydrogel; implantable sensor devices; ultrasonic; wireless sensing.