Raspberry-shaped Ga@TiO2 liquid metal particles with dual self-healing against fracture and biofouling for reusable glucose biosensor

Flexible electrochemical sensors are essential for next-generation wearable health monitoring systems, yet their long-term stability is constrained by mechanical fragility and biofouling in complex biological environments. Here, we present a dual self-healing glucose biosensor incorporating uniquely raspberry-shaped Ga@TiO 2 particles that enable both mechanical and chemical regeneration. These particles facilitate ultrasensitive glucose detection (limit of detection = 0.14 μM) via efficient redox interactions, while also enhancing the device's structural and surface resilience. The Ga@TiO 2 /PVA hydrogel sensor exhibits exceptional multilayer physical self-healing behavior, arising from the synergistic combination of PVA's dynamic hydrogen bonding and the intrinsic fluidity of the liquid metal core, maintaining 101.2 ± 4.13% of its original sensitivity after fracture healing. In addition, the sensor achieves reproducible biofouling self-healing, recovering 100.4 ± 1.35% of its initial signal after contamination, owing to the biomimetic surface morphology and self-renewing liquid metal interface. The gallium-based conductive network further ensures stable electrical performance under mechanical deformation due to its high conductivity and flow adaptability. This dual self-healing mechanism—analogous to biological tissue regeneration and self-cleaning surfaces—offers a robust strategy for constructing durable, high-performance flexible biosensors capable of reliable operation in dynamic and bioactive environments.