An Automated System for Reactive Accelerated Aging of Implant Materials with In-Situ Testing

The efficacy of implantable medical devices is limited by the longevity of devices in the body environment. Due to the aqueous and mobile-ion rich environment of tissue, robust and long-lasting encapsulation materials are critical for chronic implants. Assessing the reliability of medical devices is commonly performed through saline soak tests with reactive oxidative species at elevated temperatures and lifetime data are fit to an Arrhenius model to predict lifetime under physiological conditions. While effective, these systems often require frequent human involvement to maintain system temperature and reactive oxidative species concentration, as well as monitor sample lifetime, which makes long term testing of multiple samples difficult. Here we present an automated, low-cost, low-solution volume, and high-throughput reactive accelerated aging system to assay many thin film samples in an easy and low maintenance manner. The efficacy of up to 16 thin film coating samples can be assessed by our system through in-situ current leakage tests in a mock biological environment. We validate our system by aging thermal oxide and a-SiC thin films at 93 degrees C with 20 mM H2O2. Our system shows early failure of the thermal oxide compared to the a-SiC, in agreement with the current literature.