Photocrosslinkable starch-based polymers for ophthalmologic drug delivery.

This study focused on the development and characterization of a starch-based polymer with urethane linkages to be used as a controlled drug delivery system for biomedical applications. Starch was modified with 2-isocyanatoethyl methacrylate in order to obtain a polymer containing carbon-carbon double bonds in its structure. This modified starch was then used to produce films by UV irradiation using Irgacure 2959 (CIBA) as the photoinitiator. The modified polymer was characterized by attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The swelling capacity, in artificial lachrymal fluid (performed both at room temperature and physiological temperature), and water contact angles measurements were determined. The in vitro biodegradation in artificial lachrymal fluid supplemented with lysozyme was also studied. Scanning electronic microscopy (SEM) was used to characterize the morphology of the materials immediately after synthesis and after biodegradation. Timolol maleate and sodium flurbiprofen were immobilized by adsorption and their in vitro release profiles were followed spectroscopically.