Each year an estimated 12.7 million people need corneal donor tissue. Some common reasons for corneal damage are Fuchs’ dystrophy, keratoconus, keratitis, and acute injury. Of the 12.7 million only 1 in 70 people receive donor tissue. This has created a large demand for a synthetic biocompatible material. Keratoprosthesis, artificial corneas are only used when the recipient’s body rejects the donor tissue. Currently, the most popular keratoprosthetics are based on a polymer of MMA (methyl methacrylate). However, it is costly and eventually degrades. Preliminary results showed that a copolymer of HEMA (2-hydroxyethyl methacrylate) and MEMA (methoxyethyl methacrylate) is a possible solution. The copolymer is first polymerized using a free radical initiator, then made into a 1% solution (w/v) in ethanol. Following, the solution was spin-coated onto a cleaned quartz window and annealed at 100°C for 12 hours. This created a copolymer thin film on top of the quartz. Five different concentrations were synthesized at 0.5%, 1%, 5%, 15% and 20% MEMA in HEMA. Sum frequency generation spectroscopy (SFG) was used to understand the conformation of the copolymer’s interfacial molecules and confirm the surface segregation of the two polymer components at the surface. Meanwhile, atomic force microscopy (AFM) was used to characterize their topographical and morphological properties. Preliminary SFG results show functional groups from both constituents at the air-solid interface. In AFM, root mean squared (RMS) is a measure of the roughness of the surface. For concentrations of 0.5, 1, 5, and 15% MEMA in HEMA the average RMS is 0.3985 nm, which contrasts with the 20% which is 3.757 nm. The pore analysis suggests that this contrast is due to the size and depth of the pores. The 20% MEMA in HEMA has shown a bimodal distribution of pore depth and size. The roughness of the surface can affect the polymer's refractive index and adhesion to corneal cells.

Bulky methacrylate copolymer for keratoprosthetic application

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.