Collagen Film with Bionic Layered Structure and High Light Transmittance for Personalized Corneal Repair Fabricated by Controlled Solvent Evaporation Technique

Abstract

Corneal blindness is a common phenomenon, and corneal transplantation is an effective treatment for corneal defects. However, there is usually a mismatch between the corneal repair material and the degree of the patient’s corneal defect. Therefore, patients with different corneal defects need suitable corneal repair materials with a specific microstructure for personalized treatment. In this research, collagen films with bionic structures were fabricated through ethanol evaporation technique by regulating the volume ratios of collagen solution: ethanol = 10:0(Col)/9:1(CC91)/8:2(CC82)/CC73(CC73). Under various preparation conditions, the obtained collagen films contain layered structures of different density. SEM photos show that the CC73 film with a dense layer arrangement has a microstructure similar to that of the corneal epithelial layer, whereas the Col film has a loose layered structure similar to that of the corneal stroma layer. Four kinds of collagen films showed different optical properties and water absorption ability. A more ordered arrangement of internal layer structure leads to better mechanical properties of the collagen film. In view of this, we think that these collagen films with different microstructures and different interlayer spacing may have huge potential applications for personalized corneal repair.

Modification of Collagen Film via Surface Grafting of Taurine Molecular to Promote Corneal Nerve Repair and Epithelization Process

“…The water absorption performance of the Col-Tau film is 79.3 ± 3.5%. The results are very similar to the native cornea tissue (78.0 ± 3.0%), but significantly higher than the blank Col sample (67.9 ± 2.8%) [ 12 , 31 ]. The results indicate that the saturated water absorption of the Col-Tau film is promoted by the chemical grafting of the taurine’s sulfonic groups.…”

“…The light transmittance of the pre-wetted Col-Tau and Col sample indicate minor differences. With the increase of wavelength, the light transmittance curve of the collagen-based films reached the highest level (higher than 90%), which is very similar to that of natural cornea tissue (about 87%) [ 11 , 12 , 31 ]. In addition, Figure 5 B exhibits a picture of pre-wetted Col-Tau sample.…”

“…To mitigate this problem, many researchers have tried to prepare various artificial materials using different macromolecules to reconstruct cornea scaffolds that mimic normal corneal tissue [ 7 , 8 , 9 , 10 ]. Collagen fibrils, as the predominant component of the human cornea, with good biocompatibility, biodegradability and biological activity, have been extensively studied for corneal repair and regeneration [ 11 , 12 , 13 ].…”

Recent Approaches of Collagen Biomatrix Modification as a Corneal Biomatrix and its Cellular Interaction

“…Collagen makes up about 70% of the dry-wet of the cornea and plays an important role in supporting CECs, LESCs and corneal fibroblast cell growth [4,6,9,10,23]. Three forms of collagen biomatrix are normally used in tissue engineering research, such as collagen sponge [45][46][47][48], collagen hydrogel [49][50][51] and collagen film [52][53][54].…”

Recent Approaches to the Modification of Collagen Biomatrix as a Corneal Biomatrix and Its Cellular Interaction

“…Collagen makes up about 70% of the dry–wet weight of the cornea and plays an important role in supporting CECs, LESCs, and corneal fibroblast cell growth [ 4 , 6 , 9 , 10 , 23 ]. Three forms of collagen biomatrix are normally used in tissue engineering research, such as collagen sponge [ 45 , 46 , 47 , 48 ], collagen hydrogel [ 49 , 50 , 51 ], and collagen film [ 52 , 53 , 54 ].…”