To investigate the promoting repair effects of chitosan/gelatin electrospinning membrane implantation on conjunctival injury.

Chitosan/gelatin electrospinning membrane was prepared using electrospinning technique, and the general characteristics of the membrane was examined under the scanning electron microscope.Conjunctival injury models were established in the right eyes of 30 New Zealand white rabbits by surgical resection of 6 mm×8 mm bulbar conjunctiva, burns of weak acid at injury site and then randomized into model group, human amniotic membrane (AM) implanted group and electrospinning membrane implanted group.AM or electrospinning membrane was interlayerly implanted between conjunctiva and sclera during operation according to grouping.The inflammatory response and histopathological change at injury site were examined by slit lamp microscope and optical microscope in 4, 8, 14 and 28 days after surgery.The use and care of the animals followed by code of ethics for animal experiments at the animal experiment center of He University.

Chitosan/gelatin electrospinning membrane presented with a crosslinked network structure like AM, with the nano-microstructure of 0.1-0.5 μm fibre.No obvious inflammatory symptom was seen in the experimental eyes of various groups in 4 days after operation.In 8 days after operation, conjunctival edema and erosion were found in the model group, and slight conjunctival congestion was exhibited in the eyes of AM implanted group and electrospinning membrane implanted group.In 14 to 28 days after operation, conjunctival edema and new blood vessels were seen in the model group, and the conjunctivas were well recovered in the AM implanted group and electrospinning membrane implanted group.Histopathological examination showed dissociation, attaching, thickening and epithelization of injuried conjunctivas gradually in the model group from 4 to 28 days after operation.In the AM implanted group, attaching of AM was in 4 days, melting of AM was in 8 days, epithelization of injuried conjunctivas was in 14 days and renovation of conjunctivas was in 24 days after operation, and a rapid repairing procedure was found in the electrospinning membrane implanted group under the optical microscope.

Compared with the self-repairing process of conjunctival injury, implantion of chitosan/gelatin electrospinning membrane or AM can speed up the renovation of injuried conjunctivas, and the effects of chitosan/gelatin electrospinning membrane are better than those of AM in promoting conjunctiva repair and inhibiting scarring.

Injury, conjunctival; Conjunctival reconstruction; Biomaterials; Chitosan; Gelatin; Electrosinning chitosan membrane; Amniotic membrane; Disease models, animal