Prevention of Biofouling on Iridium Oxide Based pH Sensors Using Polyvinyl Alcohol Hydrogels

Metal-metal oxide based pH sensors such as, iridium oxide (IrOx) pH sensors have shown promise in monitoring pH for in vivo applications. In this paper, we examine the ability of PVA hydrogels in prevention of biofouling on pH sensors. This study examines the effects of biofouling on pH sensors by comparing pH sensors with and without anti-biofouling coatings made from PVA hydrogels. The results demonstrate that PVA hydrogels can be coated on the sensor surface, without affecting the sensitivity of the sensor. After coating PVA hydrogels, the rate of sensor degradation reduces without affecting the linearity of the sensor. The slope of degradation of sensitivity for the sensors coated with PVA hydrogel was 0.0038 V/pH, while it was 0.0051 V/pH without PVA coating.