Photo cross-linkable biodendrimers as ophthalmic adhesives for central lacerations and penetrating keratoplasties

PURPOSE. Biodendrimer-based hydrogel adhesives were derived from biocompatible building blocks and poly(ethylene glycol) of 3,400, 10,000 and 20,000 g/mole. The leaking pressures were determined for these adhesives when used to seal 4.1-mm central lacerations and penetrating keratoplasties (PKPs) in enucleated porcine eyes. METHODS. Three biodendrimers, ([G1]-PGLSA-MA)(2)-PEG(3,400), ([G1]-PGLSA-MA)(2)-PEG(10,000), and ([G1]-PGLSA-MA)(2)-PEG(20,000) at a range of weight percents were each photo cross-linked in the presence of a photo-initiator to form a hydrated network. These biodendrimer-based adhesives were applied directly to a 4.1-mm linear central laceration. In a PKP, the corneal button was initially secured with 8 or 16 sutures and then sealed with the adhesive. RESULTS. For the 4.1-mm central lacerations, the ([G1]-PGLSA-MA)(2)-PEG(3,400) at 20% and 40% wt/vol, the ([G1]-PGLSA-MA)(2)- PEG(10,000) at 10 and 20% wt/vol, and the ([G1]-PGLSA-MA)(2)- PEG(20,000) at 20% wt/vol held to leaking pressures above 200 mm Hg. In the autograft with 16 sutures, the 20% wt/vol of the ([G1]-PGLSA-MA)(2)-PEG(3),(400), ([G1]-PGLSA-MA)(2)-PEG(10,000), and ([G1]-PGLSA-MA)(2)-PEG(20,000) held to a pressure at or above 100 mm Hg. In the autograft with eight sutures, the ([G1]-PGLSA-MA)(2)-PEG(10,000) and ([G1]-PGLSA-MA)2-PEG20,000 formulations at 20% wt/vol held to leaking pressures of 85 22 and 80 30 mm Hg, respectively. CONCLUSIONS. The 10% wt/vol ([G1]-PGLSA-MA)(2)-PEG(10,000) formulation withheld leaking pressures above 200 mm Hg when used to secure a 4.1 mm central laceration. The 20% wt/vol ([G1]-PGLSA-MA)(2)-PEG(10,000) and ([G1]-PGLSA-MA)(2)-PEG(20,000) formulations, with 8 or 16 sutures, secured the PKP well above normal IOP. Biodendrimer-based adhesives are of potential use for repairing corneal wounds.