1. Hydrogel engineering for tissue-integratable biosensing and biocomputing
Hydrogel electrodes: Hydrogels are water-rich materials that are favorable of making commercial medical electrodes to interface with soft tissues. However, the current hydrogel electrodes suffer from limited stretchability and dehydration issues that impedes long-term use. Here, we develop skin-conformable hydrogel electrodes with high-stretchability and good water-retention ability by developing multi-network composite hydrogel materials. Read more: Advanced Materials, InfoMat.
Semiconducting hydrogel transistors: The realization of hydrogel-based transistors holds significant value for developing tissue-integratable biologics. However, its development presents challenges, primarily due to the thin-film nature of semiconductors, which are generally less than 1 micrometer in thickness. In contrast, hydrogels have greater thicknesses and struggle to achieve good semiconductor properties. Here, we develop hydrogel-transistors by developing nanocomposite semiconducting hydrogel materials that able to maintain good semiconductor behavior at extremely thick thicknesses, e.g., 100 um, which unlocks their potential for tissue-integratable biosensing and biocomputing applications. Read more: Advanced Materials.
Self-healing semiconducting hydrogels: Materials able to heal damage, like the skin, are highly desirable to improve lifetime of tissue-like devices. However, self-healing are rarely observed in conductors with thin thicknesses. Using semiconducting polymers, we developed thin film hydrogel conductors that can realize extremely fast healing (< 0.1 second), at extremely thin thickness (< 1 um), while maintaining a good semiconductor property. Here, we use these unique semiconducting hydrogels to develop self-healing electrodes and biotransistors for prolonged bioelectronic applications. Read more: Advanced Materials, Advanced Functional Materials.
2. Tissue-like organic bioelectronics (materials, physics, fabrication)
Organic electrochemical transistor (OECT) is a flagship technology among organic bioelectronic devices. It is considered as the perfect link between biology and microelectronics considering the property similarities at large. However, the mechanical mismatch at the biotic-abiotic interface causes stability issues. Here, we develop tissue-like stretchable and healable OECTs to facilitate their interfacing with soft tissues by materials development and device engineering. Read more: Chemistry of Materials, Advanced Science, Advanced Electronic Materisals, Advanced Functional Materials, Journal of Materials Chemistry C.
Funded by: University Grants Committee Germany/Hong Kong Joint Research Scheme.
3. Fully-integrated wearable system: sense, compute, control
Multi-modal biowearable systems: Despite the significant potential of organic/hydrogel bioelectronics for conformable human-centric healthcare applications, the absence of a compact readout platform impairs wearability of the entire system. We developed the PERfECT readout platform—a coin-sized, low-power, and multiplexed unit designed for wearable analysis of organic/hydrogel electrodes and biotransistors. Here, we develop multi-modal biowearable systems capable of revealing health parameters that cannot be discerned with a single parameter alone. Simultaneously, we develop closed-loop biowearables for sensor-controlled automatic medicine, such as glucose sensing and insulin injection. Read more: Analytical Chemistry, Nature.
▪️ Innovation and Technology Commission (ITC), Mainland-Hong Kong Joint Funding Scheme (National Key R&D Program, 國家重點研發計劃).
▪️ Shenzhen Science and Technology Innovation Committee (SZSTI) Shenzhen-Hong Kong-Macau Science and Technology Program (Type C).
▪️ University Grants Committee Theme-based Research Scheme.