First results of plasma sterilization tests

Full text: The research we carry out in the sterilization of different devices by means of plasma discharges seeks to generate the trained human resources to develop and promote new processes and technologies in the country. Currently, plasma corresponds to an emerging technology from which many applications have derived, many of which efficiently replace those traditionally implemented. In the case of sterilization, reactors that involve radiation or highly oxidizing and toxic agents are well known, methods that undoubtedly represent risks for the people who implement them. Plasma sterilization comes to overcome the risks presented by traditional methods. Discharges of type CD are used in which a plasma discharge is made in the entire volume of the reactor. The sterilization times are an indicator of the efficiency of the process that is implemented. These times are inevitably related to the plasma mechanisms that act in the process used as well as the type of surfaces to be sterilized, for research purposes and in the evaluation of the efficiency of the process. It is considered a blade of a surgical scalpel. The investigations have provided convincing evidence that the main sterilization factor is presented by the ultraviolet radiation of the plasma in the wavelength range between 160 nm and 240 nm as well as by the active chemical species that are generated as a result of the interactions between particles that occur within a plasma, as the power density used is relatively low, sterilization of heat-sensitive instruments is possible. It should be noted that this type of technology makes it possible for the objects to be sterilized to be immersed in the radiation source, which implies an increase in efficiency and a reduction in time, thus having a direct impact on the energy footprint of the process. In the past few days, the first tests of discharges using different gases were carried out, this allowed us to perform different tests in order to check the efficiency of the process. With the support of the Nanotechnology Laboratory, the samples (Blades of a Scalpel) were prepared with a culture of Pseudomonas; the members of this genus are generally mobile thanks to one or more polar flagella that they possess which makes it easy to identify under a microscope whether they are alive or not. Samples were exposed to different discharge times under the Glow Discharge regime throughout the reactor volume, resulting in the total death of the bacteria for exposure times greater than 2.5 minutes. The best results to date have been obtained using oxygen which is possible to explain due to the characteristic emission of this gas when generating a plasma as well as by the active chemical species that are generated when making a plasma with this gas