Protein destruction by a helium atmospheric pressure glow discharge: Capability and mechanisms

Abstract

Citation: DENG X.T., SHI, J.J. and KONG, M.G., 2007. Protein destruction by a helium atmospheric pressure glow discharge: capability and mechanisms.Journal of Applied Physics, 101 (7), article 074701, pp.1-9.Additional Information:• Biological sterilization represents one of the most exciting applications of atmospheric pressure glow discharges ͑APGD͒. Despite the fact that surgical instruments are contaminated by both microorganisms and proteinaceous matters, sterilization effects of APGD have so far been studied almost exclusively for microbial inactivation. This work presents the results of a detailed investigation of the capability of a helium-oxygen APGD to inactivate proteins deposited on stainless-steel surfaces. Using a laser-induced fluorescence technique for surface protein measurement, a maximum protein reduction of 4.5 logs is achieved by varying the amount of the oxygen admixture into the background helium gas. This corresponds to a minimum surface protein of 0.36 femtomole/ mm 2 . It is found that plasma reduction of surface-borne protein is through protein destruction and degradation, and that its typically biphasic reduction kinetics is influenced largely by the thickness profile of the surface protein. Also presented is a complementary study of possible APGD protein inactivation mechanisms. By interplaying the protein inactivation kinetics with optical emission spectroscopy, it is shown that the main protein-destructing agents are excited atomic oxygen ͑via the 777 and 844 nm emission channels͒ and excited nitride oxide ͑via the 226, 236, and 246 nm emission channels͒. It is also demonstrated that the most effective protein reduction is achieved possibly through a synergistic effect between atomic oxygen and nitride oxide. This study is a useful step toward a full confirmation of the efficacy of APGD as a sterilization technology for surgical instruments contaminated by prion proteins.

Nonthermal Plasma Inactivation of Food-Borne Pathogens

“…Vleugels and co-workers (2005) Survival of food-borne pathogens has been detected at a level of 10 5 CFU/cm 2 on stainless steel surfaces in a study by Kusumaningrum et al (2003). Deng et al (2009) showed that cold gas plasmas have the potential to denaturize proteins attached to stainless steel. Gas plasmas could also be used to remove allergens from the surface of ).…”

Plasmas meet nanoparticles—where synergies can advance the frontier of medicine

“…Such low-temperature plasmas are commonly known as cold atmospheric plasmas (CAPs) and have been shown to be capable of effectively inactivating bacteria, fungi and virus, inducing apoptosis in cancer cells, and stimulating proliferation of mammalian cells, all in a dose-dependent fashion [52] [53]. Today, CAPs are increasingly used in an impressive array of healthcare applications such as blood coagulation [58], skin disinfection [58] [59] and wound disinfection [60], wound healing [61], sterilisation of surgical instruments and medical devices [62], cancer therapy [63], and food decontamination [64]- [66]. Their potentials for healthcare are profound and their clinical successes so far are exceptionally encouraging [67][68], thus fuelling a rapid expansion of research activities in an emerging but now highly visible field known as plasma medicine.…”

1-D fluid model of atmospheric-pressure rf He+O2 cold plasmas: Parametric study and critical evaluation

“…As a result HeþO 2 plasmas are typically operated with reduced amount of oxygen and maximum process efficacy is often encountered at oxygen concentrations below 1%. 44,45 In the last decades, global models have been used to study low-pressure electronegative plasmas [46][47][48][49] and in recent years these models have been extended to the study electronegative atmospheric-pressure discharges. [15][16][17][18] In these models it is customary to assume that the input power is mainly coupled to the electrons 50 with various approximations regarding the power coupled to ions in the sheath.…”

“…As a result, atmospheric pressure plasmas are being explored for a large variety of applications including plasma medicine, [1][2][3] air purification, 4,5 sterilization, 6,7 surface modification, 8,9 and water treatment. 10,11 Many of these applications rely on the production of reactive oxygen species (ROS), which can be obtained readily in atmospheric-pressure cold plasmas in gases containing admixtures of O 2 and=or H 2 O.…”