3D printing of chitosan hydrogel reinforced with tubular nanoclay for hemostasis and infected wound healing.

Developing hydrogel dressings capable of rapid hemostasis and accommodating irregular wounds is crucial for infected wound healing. Customizable 3D-printed hydrogels, highly sought after for wound management, remain an ongoing challenge due to weak mechanical strength and low bioactivity. This work develops a nanoclay-enhanced, three-dimensional (3D) printed chitosan (CS) hydrogel for controlling bleeding and bacterial-infected wound healing. The hydrogen bonding and electrostatic attraction between halloysite clay nanotubes (HNTs) and CS endow the CS/HNTs ink with shear-thinning, excellent printability, high fidelity, and shape retention, allowing it to conform to irregular wound shapes. Incorporation of HNTs improved compressive/tensile strength and hemostatic performance of CS hydrogel. Furthermore, the antibacterial agent levofloxacin (Lev) was loaded into CS/HNTs hydrogel, which can be continuously released at the wound site to reduce inflammation and promote healing. In vitro experiments demonstrated that CS/HNTs/Lev hydrogel possesses favorable antibacterial, coagulation, blood compatibility, and cytocompatibility. Additionally, in vivo studies using infected mouse models indicated that the composite hydrogel exhibits rapid hemostatic ability, good antibacterial property, and enhanced wound healing efficacy. The 3D-printed CS hydrogel reinforced with nanoclay shows great potential as a hemostasis and wound healing dressing in clinical application.