| Description |
Biocompatibility is a key aspect in determining the success of a biomedical device. In this work the development, manufacture, designs, and biocompatibility of two devices are discussed. As protein adsorption to a material surface is the first step in the host wound healing and inflammatory response this phenomenon was additionally examined. The capsule drug ring (CDR) is a reservoir and delivery agent which is designed to be placed within the capsular bag during cataract surgery. Prototypes were manufactured by hot melt extrusion of Bionate® II (DSM), a polycarbonate urethane. The devices have been optimized using Avastin® as the drug of interest. In vitro biocompatibility was assessed with human lens epithelial cell (B-3), mouse macrophage (J774A.1), and mouse fibroblast (L-929) cell lines. Cell migration and proliferation were assessed after in vitro culture. Proinflammatory cytokines (i.e., MIP-1β, MIP-1α, MCP-1, IL-1β, TNF, and TGF-β1) were quantified using cytometric bead array (CBA). Preliminary in vivo biocompatibility and pharmacokinetics testing has been performed in rabbits. Cataract extraction uses ultrasound energy and vacuum to liquefy, emulsify, and aspirate the cloudy lens. During phacoemulsification, thermal energy and fluidic currents within the eye can damage the postmitotic corneal endothelium. This results in corneal edema, compromised vision, and a potential need for corneal transplantation. Viscoelastics are used to stabilize the anterior chamber, to maintain the eye pressurization, and to help absorb and dissipate thermal energy. However, the fragile corneal endothelium is often damaged despite the use of viscoelastics. This work discusses the development of a foldable 100 micron transparent shield for use during phacoemulsification. This endo-contact lens is designed to float in the anterior chamber to allow for surgical access, and to absorb and deflect thermal energy to protect the fragile corneal endothelium. |
