Purely Zwitterionic Polymer Injectable Hydrogels for Vitreous Substitutes

• • PCBUIA hydrogels exhibit density (1.016–1.021 g/cm³), refractive index (1.3359–1.3389), and transmittance >90%, matching native vitreous; this optical and physical parity is critical for avoiding visual distortion and maintaining retinal imaging fidelity in clinical vitrectomy. • • The supramolecular network enables shear-thinning injectability and rapid self-healing, allowing minimally invasive delivery through small-gauge needles; this reduces surgical trauma and operating time compared to silicone oil injection, which requires larger incisions and postoperative positioning. • • Ultralow protein adsorption and suppressed cell attachment were confirmed in vitro, and no foreign-body reaction or fibrotic capsule formation occurred in vivo; this antifouling property directly addresses the inflammatory and fibrotic complications that limit current substitutes like silicone oil. • • After one month in rabbit eyes, PCBUIA hydrogels maintained optical transparency, preserved retinal morphology, and did not elevate intraocular pressure or cause inflammation; this short-term biocompatibility establishes a foundation for clinical translation, though long-term stability beyond one month remains unverified.