A Wet-Adhesive Hydrogel Patch with Rapid-Adhesion, Anti-Swelling, and Pro-Healing Properties for Sutureless Repair of Dural Tear.

Dural tears and subsequent cerebrospinal fluid leakage are common and intractable in spinal surgery. However, the existing clinical treatments are still unsatisfactory and the effective closure and repair of dural tears remain a huge challenge. Herein, a bilayer wet-adhesive hydrogel patch (denoted as BMTP) with rapid-adhesion, anti-swelling, and pro-healing properties is developed, which comprises a tough poly(vinyl alcohol) (PVA) dissipative layer and a functionalized poly(acrylic acid)-based wet-adhesive layer modified with methyl acrylate (MA) and tannic acid (TA). Owing to the hydrophobic effect of MA moieties and the strong intermolecular hydrogen bonding interaction facilitated by TA, BMTP has a unique low swelling property (24.2%) without compromising wet adhesion. Meanwhile, attributed to the high mechanical strength of the PVA dissipative layer and its mechanical interlocking with the wet-adhesive layer, BMTP exhibits durable sealing capacities with a burst pressure tolerance of 325 mm Hg. Moreover, the TA-mediated promotion of fibroblast proliferation enables BMTP to accelerate the healing of dura wounds. The rabbit dural tear model demonstrates that the BMTP can effectively seal and promote the healing of the damaged dura without postoperative adhesion within 3 weeks. Therefore, this work may offer a promising solution for the sutureless treatment of dural tears.