Hydroxyl Radical Scavenging of Liquid Silicone Rubber/Ce_0.5Zr_0.5O₂ Nanocomposites for Local Delivery of Antioxidants to Control Oxidative Stress Induced Damages

Local administration of drug effectively following cochlear implantation is highly challenging, which imposes limitations such as insufficient drug, poor distribution and need for additional surgical procedures. Recent research is focused on integrating the drug with the silicone encasing of the electrode in cochlear implanted patients to overcome these limitations. The objective of the study is to assess the delivery of Ce_0.5Zr_0.5O₂ antioxidant through silicone encasing and the suitability of the nanocomposites as an electrode encasing material. The proposed strategy is expected to overcome the issues associated with poor dispersion stability of the Ce_0.5Zr_0.5O₂ based nanofluid and its corresponding long term effect, while utilizing its regenerative ability. Liquid silicone rubber (LSR)/Ce_0.5Zr_0.5O₂ nanocomposites are prepared and characterized using suitable techniques. The reinforcement of nanoparticles up to 5 wt.% did not affect the modulus and electrical conductivity significantly. The hydroxyl radicals are scavenged by 36% in artificial perilymph fluid. The Ce³⁺ concentration is reduced from 45 to 9% after adding H₂O₂ and then it is regenerated to 35% after 13 days due to its ability to switch between Ce³⁺ and Ce⁴⁺. From this study, LSR/ Ce_0.5Zr_0.5O₂ nanocomposites are proposed as electrode encasing material inside cochlea for scavenging hydroxyl radicals and its regeneration potential.