Cornea stroma-mimicking films derived from cellulose nanocrystal templating fibrous collagen as therapeutic contact lenses

Multilayered films were fabricated from the dilute mixtures of collagen (Col) and dialdehyde cellulose nanocrystals (DAC) with various oxidation degree (OD%) via vacuum filtration. The anisotropic nanocrystal was able to template the alignment of collagen fibrils to mimic the collagen plywood of cornea stroma. DACs possessed good crystallinity and uniform size after the periodate oxidation. With increasing OD% from 0% to 56.6%, C/DC (Col/DAC) films showed an increase in transparency but a decrease in water content and oxygen permeability. C/DC films in the wet and dry state performed with opposite trends in the mechanical properties including modulus, stress, and strain with the increase of OD%. With increasing Col-DAC ratio from 0.2 to 5.0, C/DC films displayed an increase in water content and mechanical properties but a decrease in transparency. Drug-laden film displayed a sustained release of the anti-inflammatory agent in artificial lacrimal fluid (ALF) within 1 week. It also showed an improved bioava...