A PEG-Lysozyme hydrogel harvests multiple functions as a fit-to-shape tissue sealant for internal-use of body.

In situ formation of surgical sealants to stop internal fluids leakage is more attractive compared to the traditional suture or staple. However, commercial sealants have weak points in tissue adhesive, cell affinity, antibacterial etc., which make them remain suboptimal for internal use of body. It is required to develop multifunctional sealants that can meet clinical needs. Herein, a PEG-lysozyme (LZM) injectable sealant composed of 4-arm-PEG and lysozyme was developed. Lysozyme offers free amine groups to rapidly cross link with PEG. The hydrogel can tightly adhere to tissues and provide good mechanics to withstand high pressure. Moreover, lysozyme innately confers antibacterial and cell affinity on the hydrogel that are usually lacking in marketed sealants. The hydrogel is easily operated to seal gas or blood leakage in a rabbit trachea and artery defect. Moreover, it can close the transmural left ventricular wall defect on a beating heart. The traumatic organ functions completely recovered postoperatively. Considering the good biocompatibility and the simple fabrication process, the PEG-LZM hydrogel is promising to clinical transformation. More broadly, our work indicates that nature-occurring molecules are versatile building blocks for construction of materials and confer functions, which represents a simple tragedy to develop advanced functional biomaterials.