Spidroin-based multifunctional microneedles with controlled drug release for efficient wound management

Wound healing remains a serious challenge in the biomedical field due to its complex physiological processes. To address this issue, microneedle patches are proposed as an effective strategy for wound management. Herein, we propose novel breathable microneedle patches containing therapeutic drugs and functional materials for wound healing, which are fabricated using extrusion 3D printing technology. The microneedle patch is composed of needle tips and a breathable scaffold backing layer made of spidroin hydrogel, polyurethane, and aloe vera gel, providing excellent biocompatibility and self-healing ability. Furthermore, eutectic Galium-Indium (EGaIn) was incorporated into the dressing, enabling the near-infrared light response function. The highly efficient photothermal conversion allowed for superfast self-healing in seconds. The microneedle dressing was sensitive enough to monitor large-scale movements at different joints and small-scale motions of the throat during swallowing. Combining biocompatible microneedles with a temperature-responsive hydrogel (pNIPAM), stable controllable drug delivery is achieved using near-infrared (NIR) light. The stable photothermal performance enabled the device to release a controlled dose of the drug over multiple light triggers. With NIR-triggered pulse drug release, VEGF-mediated treatment on wound healing was significantly improved in mouse models by accelerating tissue repair and reducing the inflammatory response.