Improvement in mechanical properties of corneal bio-ink using Crystalline Nano Cellulose

Abstract

The ability of transmittance and tensile strength are critical for the tissue engineered cornea. We have previously demonstrated keratocytes exhibited high gene expression of positive marker in the corneal de-extracellular matrix (Co-dECM) gel. However, the mechanical properties of this bio-ink is different from that of the native human cornea. Here we enhanced the mechanical strength of Co-dECM gel using the Crystalline Nano Cellulose (CNCs). Furthermore, transmittance increased with CNCs. The 2% Co-dECM gel was mixed with 0.25wt% CNCs, which was used to encapsulate cells. The gelation of resultant material underwent; a thermal crosslinking at 37℃ for 30minutes and a chemical crosslinking by treating calcium chloride. The results revealed that the addition of CNCs reinforced the tensile strength of Co-dECM gel by twice, and increased the transmittance by 10%. Moreover, the hybrid material is not detrimental to the viability of entrapped cells. Using such a bio-ink, we can envision a tissue-engineered cornea with sufficient strength and could supersede the animal tests for drug screening and toxicology applications.