Tiny Wearable Biosensing Platform


The University of Hong Kong (HKU) Faculty of Engineering researchers have created a coin-sized device that can sense weak electrochemical signals and be utilized for individualized health monitoring and evaluation of disorders like diabetes, cardiovascular diseases, and mental health. The Journal of Analytical Chemistry’s cover featured the discovery.

The Personalised Electronic Reader for Electrochemical Transistors, or PERfECT System, is the smallest device of its kind in the world, measuring 1.5 cm by 1.5 cm by 0.2 cm and weighing only 0.4 gram. It can be readily worn, for example, as a patch or linked with a smartwatch to provide continuous monitoring of bio-signals such as blood glucose levels and antibody concentrations.


The wearable device developed by the team is incredibly small, soft, and undetectable to wearers, and it can continually monitor the wearer’s health, according to Dr. Shiming Zhang of the Department of Electrical and Electronic Engineering, who is also the group’s leader. It has the potential to revolutionize healthcare technology because of these properties.


The innovation represents a significant advancement for organic electrochemical transistors, which are regarded as the next-generation sensing technology due to their water stability and high sensitivity at low operating voltages (milli-volts), but which, up until now, lacked a miniature wireless system to operate within.


With a data sampling rate as high as 200 kilo-samples per second, the PERfECT wearable system fills this void with its ability to properly characterize the overall performance of the electrochemical transistor, a performance on par with bulkier commercial equipment. However, the cost is merely 10% of the commercial price. It may also measure the outputs of other varieties of low-voltage transistors, such as electrolyte-gated field effect transistors and high-k dielectric-gated thin-film transistors, and act as a miniature electrochemical station for wearable technology.


The system could be used right away in numerous low-voltage transistor-based wearable systems. SESIC, a start-up business founded by Dr. Zhang’s team, was created to make the technology available.


The PERfECT system was developed as a result of the distinctive, interdisciplinary culture in the HKU WISE Research Group, which includes researchers from electrical engineering, applied chemistry, biomedical engineering, microelectronics, and software engineering, according to Dr. Zhang, who has been working on wearable technologies for digital healthcare since 2013. Dr. Zhang also made it a point to assemble a team of bright, youthful undergraduate and graduate students.


The WISE students have received numerous accolades for their inventive developments in wearable health tech, including the Materials Research Society (MRS) Best Presentation Award (2021 Fall), the IEEE Engineering in Medicine Award, and the Hong Kong Academy of Engineering Sciences (HKAES) 2021-22 University Pitch Competition on Global Grand Challenges, which qualified them as one of only five teams from China for the International Student Competition of the 5th Global Grand Challenges Summit (winning twice, 2021&2022).


According to Professor Zhang, WISE will aim to further the shift from “hospital-centric” to “human-centric” healthcare by creating cutting-edge wearable, intelligent, and soft electronics technologies. Pushing OECTs Toward Wearable: Development of a Miniaturized Analytical Control Unit for Wireless Device Characterization is the title of the research study that was published in Analytical Chemistry.