Poly (hydroxyethyl methacrylate-co-hydroxyethyl acrylate) soft contact lenses for acetazolamide release

In this study, different ratios of poly (hydroxyethyl methacrylate-co-hydroxyethyl acrylate) hydrogels (HEMA-co-HEA), corresponding to (100/0, 70/30, 60/40, 50/50, 40/60, 30/70, and 0/100) were successfully prepared by free radical polymerization leading to tunable drug release materials for therapeutic soft contact lenses (SCLs) applications. The microstructures of the materials were investigated using Fourier transform infrared (FTIR) spectroscopy and scanning electron microscopy (SEM), and their thermal properties were examined with differential scanning calorimetry (DSC) and thermogravimetric (TGA) analyses. The results showed that the presence of HEA in the hydrogels matrix improved the materials’ microstructure and enhanced the swelling capacity in a 0.9% NaCl solution (pH = 5.5) at 37 °C. Furthermore, in vitro study of the loading and release of acetazolamide, as a model drug, showed a non-Fickian drug release behavior for all the studied hydrogels, whereas the highest drug release/loading capacity was observed for the hydrogel ratio HEMA/HEA of 40/60. Therefore, it can be concluded that the corresponding hydrogel is a promising curative SCLs material for a sustainable drug release application.