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

ABSTRACT Ethylene oxide and gamma irradiation are two well-established sterilizing processes for surgical materials; however, they present toxicity and high cost, respectively. Ozone Gas, O3(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 °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 O3(g), and O3(g) alone group. The CFU/mL count demonstrated microbicide efficacy of LP+O3(g) and O3(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.