Use of a low-pressure plasma discharge for the decontamination and sterilization of medical devices

Abstract

Nonequilibrium low-pressure plasma discharges are extensively studied for their applications in the field of decontamination and sterilization of medical devices. The aim of this contribution is to discuss and demonstrate feasibility of oxygen low-pressure inductively coupled plasma (ICP) discharges for removal of various kinds of biological contamination. We demonstrate the ability of ICP discharges for the sterilization of bacterial spores and the removal of biological contamination from proteins and pyrogens.

Elimination of Biological Contaminations from Surfaces by Plasma Discharges: Chemical Sputtering

“…Nevertheless, those pioneering studies clearly demonstrated the possibility to eliminate different proteins [14, 20, 21, 23-25, 28, 45, 46] and bacterial endotoxins [15,[17][18][19]45] from surfaces by plasma treatment and reported chemical and morphological changes of the treated biomolecules induced by plasma discharges. Those studies also indicated that effective elimination of biomolecules can be achieved preferably within an active plasma sustained in oxygen-containing discharge mixtures.…”

NanoSIMS50 analyses of Ar/18O2plasma-treatedEscherichia colibacteria

“…Energy dissipation in plasmas leads to the formation of electrical charges, excited neutral species, radicals, photons and gas heating, among others, and all these components can play an important and synergetic role in decontamination processes [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Nevertheless, interaction mechanisms between plasmas and micro-organisms are still not fully understood [1,16,17].…”

Inactivation of Bacteria by Non-Thermal Plasmas

“…Taking into account the high efficiency of oxygen-based plasmas, literature on low pressure sterilization has mainly focused on these kind of plasmas, nevertheless, inert gas plasmas are in some cases still employed for bacterial inactivation (Liu&Chen, 2008. Recently, many studies (Bol'shakov et al, 2004, Boscariol et al, 2008, Cvelbar et al, 2006, Nagatsu et al, 2003, Rossi et al, 2008, Singh et al, 2009, Vicoveanu et al, 2008 on the effects of pure oxygen vacuum plasmas on bacteria have been conducted. Bol'shakov et al (Bol'shakov et al, 2004) published an interesting paper on the use of an oxygen RF plasma for sterilization purposes.…”

“…The study was carried out for two operational modes: the inductively coupled mode and the capacitively coupled mode and it was found that the inductive mode offers a better efficiency in destroying bacterial cells. Rossi et al (Rossi et al, 2008) also employed a low pressure oxygen RF discharge for the inactivation of B. stearothermophilus. Figure 8 presents scanning electron microscopy (SEM) images of the untreated spores and spores exposed to the oxygen discharge.…”