Intraocular-microenvironment responsive fluorescent hydrogels in rhegmatogenous retinal detachment repair

Rhegmatogenous retinal detachment (RRD) is a severe eye condition that can threaten vision without proper treatment. The primary treatment for RRD is vitrectomy, however, the postoperative requirement for a prone position, coupled with unsatisfactory retinal reattachment rates, presents a significant clinical challenge. Recent advancements in technology and material engineering have led to the development of specific biomaterials serving as retinal patches that can seal retinal breaks. Whereas, existing materials still face limitations including the need for specialized implantation instruments and complex surgical operations for certain materials, inadequate conformability to the eyeball due to relatively high material rigidity that impairs sealing performance, and poor biocompatibility. To overcome these difficulties, herein we introduce a novel fluorescent hydrogel composed of 4-arm-PEG-Mal and 4-arm-PEG-SH as a retinal sealant. This innovative material undergoes rapid gelation in response to the weakly alkaline intraocular environment following injury, enabling effective sealing of retinal breaks and the surrounding area. Furthermore, the hydrogel's inherent fluorescent property provides enhanced intraoperative visibility. Evaluated in a rabbit model of retinal detachment, the hydrogel demonstrated efficient therapeutic treatment in promoting RRD repair, while offering significant visual and surgical advantages. In conclusion, the retinal break-sealing hydrogel developed in this work presents a promising new strategy for the treatment of RRD, with considerable potential for clinical translation.