Chitosan-Based Microneedle Patch with Multi-Anchoring and Integrated Hemostatic Mechanisms for Highly Efficient Bleeding Control in Dynamic, Wet Intestinal Conditions.

Abstract

Severe intestinal bleeding poses life-threatening risks, including hemorrhagic shock, organ damage, infection, and death. Current hemostatic materials struggle to adhere to wet, dynamic intestinal tissues, hindering effective hemostasis. Inspired by the hookworm's rigid mouthpart and flexible body, which enable robust anchoring in the intestine, we developed a hydrogel microneedle patch (40K@P/G MNs) integrating multianchoring and hemostatic mechanisms. The patch leverages microneedle topology and gallic acid-grafted chitosan for enhanced mucosal adhesion, coupled with an extensible backing layer of optimized elasticity, achieving robust tissue adhesion (86.17 ± 26.19 mm Hg) in porcine intestinal models. The patch enhances clotting through a synergistic mechanism involving both chitosan and kaolin, which collectively promote platelet adhesion and activate the coagulation cascade, yielding a low blood coagulation index (4.92 ± 0.68%). It demonstrated excellent hemostatic performance in a rat liver hemorrhage model, achieving hemostasis within 35 s and preventing rebleeding. Its backing layer matches the intestine's mechanical stress, providing elasticity to withstand peristaltic forces. This multianchoring microneedle patch offers a carbohydrate-based solution for rapid, localized hemostasis in challenging intestinal environments.