Inactivation of Staphylococcus aureus in Surgical Needles by Exposure to Ozone Gas and Low Pressure

摘要

Ethylene oxide and gamma irradiation are two well-established sterilizing processes for surgical materials; however, they present toxicity and high cost, respectively. Ozone Gas, O-3(g), has been used effectively for disinfection and sterilization. Low pressure (LP) can promote water vaporization whenever the vapor pressure drops below the water saturation pressure, which at 20 degrees C (experimental temperature) is 2337 Pa. The microorganism used to contaminate the surgical needles (SN) was Staphylococcus aureus, a gram-positive bacterium whose cytoplasm is mostly water. Sixty SN samples were divided into six groups of 10: negative control (sterile SN), positive control (experimentally contaminated SN), LP group, two groups associating LP and O-3(g), and O-3(g) alone group. The CFU/mL count demonstrated microbicide efficacy of LP+O-3(g) and O-3(g) groups. This is an innovative protocol for microbial inactivation, mainly because of LP application. In the future, this technique can be evaluated for sterilization of SN and other medical devices.