Atmospheric plasma jet for surface treatment of biomaterials

Abstract

A direct current (DC) powered low-temperature atmospheric pressure plasma (LTAPP) jet device was built and used to sterilize Escherichia coli (E.coli) bacteria. The plasma jet's general properties, such as length and temperature, were first tested and found to be strongly related to the plasma jet's operational flow mode (laminar or turbulent flow). The optical emission spectra of various gas mixtures were measured to confirm the presence of active radicals, which is critical for sterilization success. Pure helium gas or a combination of helium with a small percentage of oxygen (6.25 %) was found to have the highest intensities of bactericidal species such as atomic oxygen (O) and hydroxide (OH). These mixtures were then used to treat E.coli bacteria previously grown in a Petri dish. Sterilization was accomplished by repeatedly treating the bacteria for 10 seconds for 5-10 rounds for short periods. The best results were obtained when the bacteria had enough time to rest between rounds.

In Vitro and In Silico Studies of Functionalized Polyurethane Surfaces toward Understanding Biologically Relevant Interactions

“…Recently, cold plasmas have proved effective for material functionalization, owing to their good performance at close-to-ambient temperatures. − The major advantage of plasma treatment, compared with the “wet chemistry” method, is its versatility, as it is not limited to a specific polyurethane structure. However, the treatment parameters need to be adjusted individually for each material, considering, for example, its chemical composition, crystallinity, and thickness.…”