Injectable hyaluronic acid-collagen derived hydrogel based on component biomimetic as vitreous substitute

• The integrity of HA structure is protected by “indirect oxidation” method. • The hydrogel shows the properties matching with the natural vitreous. • The hydrogel has excellent biocompatibility. • Better tamponade effect is reflected in hydrogel compared with SO after vitrectomy. Vitrectomy is a common clinical treatment for fundus disease. Due to the non-renewable nature of the vitreous, artificial vitreous are usually required to replace natural vitreous to perform functions post operation. Silicone oil and gas, as the most commonly used vitreous substitutes, have obvious drawbacks, which may lead to postoperative posture maintenance, visual impairment, cataract formation and secondary surgery. In this study, an in situ cross-linked bionic hydrogel (OAHA-CDHA/Col) based on hyaluronic acid (HA) and collagen (Col) with available gelling time for clinical operation, excellent self-healing and fatigue resistance, as well as suitable mechanical and optical properties is constructed. The compatibility and degradability of OAHA-CDHA/Col hydrogel are verified, as well as the feasibility as vitreous substitute in rabbit vitrectomy model. Notably, the hydrogel demonstrates improved intraocular tolerance compared with silicone oil, with no cataracts, endophthalmitis, fundus lesions and other complications observed. These findings position the OAHA-CDHA/Col hydrogel as a promising candidate for an ideal vitreous substitute.