Synergetic inactivation of Staphylococcus epidermidis and Streptococcus mutans in a TiO2/H 2O2/UV system

摘要

TiO 2 photocatalysis can be used to kill surface adherent bacteria on biomaterials, and is particularly interesting for use with percutaneous implants and devices. Its efficiency and safety, however, depend on the activation energy required. This in vitro study investigates synergetic effects against the clinically relevant strains S. epidermidis and S. mutans when combining photocatalytic surfaces with H 2O 2. After 20 min exposure to 0.1 wt% H 2O 2 and UV light on TiO 2 surfaces, viabilities of S. epidermidis and S. mutans were reduced by 99.7% and 98.9%, respectively. Without H 2O 2 the corresponding viability reduction was 86% for S. epidermidis and 65% for S. mutans. This study indicates that low concentrations of H 2O 2 can enhance the efficiency of photocatalytic TiO 2 surfaces, which could potentially improve current techniques used for decontamination and debridement of TiO 2 coated biomedical implants and devices.