Cold Argon Research Articles

Cancer therapy system based on gold nanoparticle / cold plasma via stimulated singlet oxygen production

Gold nanoparticles have unique physical/chemical properties which let them very useful in several applications. In addition, to their biocompatibility which is very important for biomedical applications. Recently gold nanoparticles and reactive species of cold plasma have been successfully used for tumor cells and cancer treatment. This method depends on the type of reactive ionized species or the size of gold nanoparticles which it produces and its directed effect on the cell cycle. Our proposed novel designed system which combines both gold nanoparticles and reactive species of nitrogen and argon cold plasma is obtained. Therefore, generating singlet oxygen and reactive species with confirming gold nanoparticles stability as well as to its exposure to cold plasma at different conditions and time periods is accomplished. The analysis of this system will be done using Raman spectroscopy technique. This procedure will enhance better, direct, effective and selective targeting for different kinds of bio-threats such as tumor cells, bacteria, fungi, and virus. This innovative system may be used as a new sterilized technique for different fields such as medical and biological sector, and more promise as cancer therapy selective technique.

Surface and rheological properties of egg white albumin/gelatin dispersions gelled on cold plasma-activated glass

Thin layers of egg white albumin/gelatin gel have been formed on glass plates previously treated by cold plasma, using oxygen, air and argon gases. After gelation, the gels were detached from the support and the inner surface previously attached to the plate was investigated. Water contact angles were measured on the detached films and their wettability studied in terms of surface free energy changes induced by the contact with the glass support treated with different gases cold plasma. The effect of increasing concentration of gelatin in the gel was also studied. Pre-treatment with oxygen plasma manifested the most significant changes of wetting properties of the films. A novel method was applied to obtain samples with the same thickness and the viscoelastic properties were measured. As expected, increasing gelatin concentration caused the formation of stronger (higher G*) gels. Gels formed on oxygen plasma treated glass support were the strongest. Optical profilometry was used for the characterization of the gels surface topography. It was found that the surfaces become rougher with the plasma treatment of glass support, no regard which gas was used. Increased roughness of the gels caused a decrease in the contact angles. This paper shows, for the first time in the literature, that even when the gel is not treated directly by cold plasma, but it is obtained on pretreated support, it is an effective method to change its surface and rheological properties.

Cold Argon Plasma as Adjuvant Tumour Therapy on Progressive Head and Neck Cancer: A Preclinical Study

Investigating cold argon plasma (CAP) for medical applications is a rapidly growing, innovative field of research. The controllable supply of reactive oxygen and nitrogen species through CAP has the potential for utilization in tumour treatment. Maxillofacial surgery is limited if tumours grow on vital structures such as the arteria carotis. Here CAP could be considered as an option for adjuvant intraoperative tumour therapy especially in the case of squamous cell carcinoma of the head and neck. Further preclinical research is necessary to investigate the efficacy of this technology for future clinical applications in cancer treatment. Initially, a variety of in vitro assays was performed on two cell lines that served as surrogate for the squamous cell carcinoma (SCC) and healthy tissue, respectively. Cell viability, motility and the activation of apoptosis in SCC cells (HNO97) was compared with those in normal HaCaT keratinocytes. In addition, induction of apoptosis in ex vivo CAP treated human tissue biopsies of patients with tumours of the head and neck was monitored and compared to healthy control tissue of the same patient. In response to CAP treatment, normal HaCaT keratinocytes differed significantly from their malignant counterpart HNO97 cells in cell motility only whereas cell viability remained similar. Moreover, CAP treatment of tumour tissue induced more apoptotic cells than in healthy tissue that was accompanied by elevated extracellular cytochrome c levels. This study promotes a future role of CAP as an adjuvant intraoperative tumour therapy option in the treatment of head and neck cancer. Moreover, patient-derived tissue explants complement in vitro examinations in a meaningful way to reflect an antitumoral role of CAP.

Cold atmospheric argon plasma jet source and its application for bacterial inactivation

In this work, the efficiency of inactivation of a cold argon plasma jet at atmospheric pressure (APPJ) on the basis of a low-current spark discharge into microorganisms with different characteristics of the cell walls was evaluated. Gram-negative bacteria Escherichia coli M17, gram-positive bacteria Bacillus subtilis 534 and Bacillus cereus IP 5832, and the yeast Saccharomyces cerevisiae were seeded on cultured Petri dishes. A plasma jet with an average power of 0.85 W and a flow rate of argon of 6.7 l/min was directed perpendicular to the Petri dishes with agar. The distance to the agar varied from 0.5 to 3 cm, and the treatment time varied from 5 to 300 s. The efficiency of inactivation was assessed by measuring the area of inactivation zones (where there was no growth of microorganisms). It was shown that gram-negative bacteria E. coli M17 is most susceptible to exposure to the plasma jet, and gram-positive bacteria B. cereus IP 5832 and yeast S. cerevisiae are most stable. It is established that an increase in the treatment time of plasma jets of a low-current spark allows effective inactivation of microorganisms over a much larger area.

Cold plasma poration and corrugation of pumpkin seed coats

The treatment of seeds and plants by electrically generated cold atmospheric pressure plasma can accelerate seed germination and radicle growing rates. The plasma generated reactive oxygen and nitrogen species, UV photons, and high frequency electromagnetic fields can penetrate into seed coats and modify their surface properties. Atomic force microscope data shows that cold helium or argon plasma induces strong corrugation of pumpkin seed coats, produces pores and surface defects. These structural deformations and poration enhance water uptake by seeds during the imbibing process, accelerate seeds germination, and increase seed growth. The cold atmospheric pressure plasmas treatment of pumpkin seeds also decreases the apparent contact angle between a water drop and the seed surface, thereby improving the wetting properties of seeds surfaces. Magnetic resonance imaging studies show acceleration of water uptake in pumpkin seeds exposed to a cold plasma jet. Reactive nitrogen and oxygen species, high frequency electromagnetic fields and photons emitted by the plasma jets accelerate germination of pumpkin seeds both independently and synergistically. These results show that cold plasma can be used in agriculture for acceleration of seed germination, increasing growth of plants seedlings, poration and corrugation of the bio-tissue surfaces.

Effect of different plasma treated zirconia on the adhensive behaviour of human gingival fibroblasts

OBJECTIVE To evaluate the effect of different cold atmospheric plasma (CAP) treatment on the surface chemical and physical properties of zirconia and adhensive behaviour of human gingival fibroblasts (HGFs) cultured on zirconia disks. METHODS The zirconia disks were divided into four groups and treated using helium, argon and mixture of argon and oxygen cold atmospheric plasma for 90 s or left untreated. The surface morphology, wettability and chemical elements were analyzed right after treatment. Human gingival fibroblasts were grown from biopsies obtained from a periodontally healthy human subject during periodontal surgery. HGFs were seeded on zirconia disk, and cells density was measured at the time point of 3 hours. Indirect immunofluorescence (IIF) was performed for morphometric examination at the time point of 3 hours. RESULTS The crystallographic structure of zirconia was analyzed previously and the results suggested that it fitted the properties of zirconium yttrium oxide. After helium, argon and mixture of argon and oxygen cold atmospheric plasma treatment, the surface morphology and roughness of zirconia disks remained the same. The contact angle of zirconia decreased significantly(P<0.05)after CAP treatment: from 68.38° to 17.90°. After different CAP plasmas treatment, the atomic percentage of carbon on the outermost surface of the three groups decreased, as did the surface C/O ratio. The surface C/O ratio of zirconia decreased from 1.07 to 0.33. Fibroblasts density increased on CAP treated disks, especially the ones treated by mixture of argon and oxygen CAP(P<0.05). Cells of the three CAP plasma treatment groups spread better and had more protrusions, as well as larger surficial areas. CONCLUSION Based on the results of this study after being treated by different kinds of CAP plasmas for 90 s, the surface wettability increased and the elements changed significantly with no changes in the tomography and roughness of the materials. The CAP treatment enhances the adhensive behavior of fibroblasts on zirconia by increasing the oxygen functional groups and promoting the cell density. Wettability of zirconia, an important physicochemical property, has a vital influence on the cell behaviors.

Efficient charge transport in surface engineered TiO2 nanoparticulate photoanodes leading to improved performance in quantum dot sensitized solar cells

Cold argon plasma treated TiO2 nanoparticulate photoanodes have been utilized for fabrication of quantum dot sensitized solar cells (QDSSCs). After plasma treatment the TiO2 nanoparticles got assembled in a closely spaced manner with increase in surface roughness factor owing to surface etching by the highly energetic ions, electron and radicals present in the plasma output. The photoanodes possess high inter-particle contact delivering fast charge carrier transport network minimizing the loss of charge carriers. The increase in conductivity was probed through conducting-AFM measurements. This morphological variation significantly inhibits the interfacial recombination by 3.5 times at the TiO2/NC/electrolyte interface as confirmed through electrochemical impedance spectroscopy. Moreover, the increase in Ti3+ as suggested by X-ray photoelectron spectroscopy also contributes in the enhancement of conductivity providing additional electron donor states. The power conversion efficiency increased from 3.65% to 5.01% for CdSe0.4S0.6 alloy nanocrystals (NCs) sensitized solar cells utilizing these plasma treated TiO2 photoanodes. Thus our strategy paves promising direction for the efficiency enhancements in QDSSC devices.

Formation of double-layer in the early stage of nanosecond laser ablation

Relying on classical spectroscopy we investigate the early stage of ablation process and expansion of plasma induced on copper target by 532 nm harmonic of Nd:YAG laser. The experiment is done at reduced atmosphere pressure 2–50 Pa. Radially resolved spectroscopy is employed for expansion velocity estimation and monitoring fluorescence of surrounding gas. We show, relying on probe measurements, that emission of the fast electrons starts during the laser pulse duration. In less than 30 ns and on 1 mm scale ions reach velocity of ∼ 50 km/s or ∼ 800 eV energy. It suggests that electrons, during the laser action, have to gain more than 800 eV energy from the laser radiation to maintain the charge separation. We show that the expansion velocity of ions/atoms is proportional to their charge, Cu++ ions are faster than Cu+ ions and Cu atoms. These results are in consistence with double-layer model. The spectrum emitted from the cold argon region consists only of very narrow Ar I and Ar II spectral lines while the hot plasma plume, during the initial stage, radiates continuous spectrum in the investigated range 200–650 nm.

Ferrous chloride and ferrous sulfate improve the fungicidal efficacy of cold atmospheric argon plasma on melanized Aureobasidium pullulans

Since cold atmospheric pressure plasma (CAP) has not only bactericidal activity but also fungicidal activity without toxic residues and thermal damage, it is considered as an alternative method for sterilization of fungi on the surfaces of perishable foodstuffs and human bodies. Aureobasidium pullulans is a ubiquitous yeast-like fungus and called black yeast because it produces melanin, a dark biological pigment. It is well known that various melanized fungi show hyper-resistance to extreme stress conditions including high levels of radioactivity. Curiously, however, there is very little information about the fungicidal effects of CAP on melanized fungi. Therefore, we herein investigated the effects of CAP on A. pullulans, using cold atmospheric argon plasma (Ar plasma). We found that ammonium sulfate repressed the synthesis of melanin in A. pullulans as well as Aureobasidium melanogenum. Although the non-melanized A. pullulans cells were efficiently killed by the exposure of Ar plasma, the melanized cells showed the significant resistance to Ar plasma as well as to hydrogen peroxide and thermal stress. In order to improve the fungicidal efficacy of Ar plasma, we examined the combination of Ar plasma and Fenton reaction. We realized that FeCl2 and FeSO4 significantly improved the sterilization efficacy of Ar plasma on the melanized A. pullulans.

Modification of Immobilized Titanium Dioxide Nanostructures by Argon Plasma for Photocatalytic Removal of Organic Dyes.

The aim of this study was to modify surface properties of immobilized rutile TiO2 using Argon cold plasma treatment and to evaluate the performance of the catalyst in photocatalytic elimination of synthetic dyes in UV/TiO2/H2O2 process. The surface-modified TiO2 was characterized by XRD, EDX, SEM, UV-DRS and XPS analyses. Response surface methodology was adopted to achieve high catalyst efficiency by evaluating the effect of two main independent cold plasma treatment parameters (exposure time and pressure) on surface modification of the catalyst. The increase of the plasma operation pressure led to higher decolorization percentage, while the increase of plasma exposure time decreased the decolorization efficiency. RSM methodology predicted optimum plasma treatment conditions to be 0.78 Torr and 21 min of exposure time, which resulted in decolorization of 10 mg/L solution of the malachite green solution by 94.94% in 30 min. The plasma treatment decreased the oxygen to titanium ratio and caused oxygen vacancy on the surface of the catalyst, resulting in the superior performance of the plasma-treated catalyst. Pseudo first-order kinetic rate constant for the plasma-treated catalyst was 4.28 and 2.03 times higher than the rate constant for the non-treated photocatalyst in decolorization of aqueous solutions of malachite green and crystal violet, respectively.

The eliminatory effects of cold argon plasma jet on aflatoxin B1 produced by different isolates of Aspergillus section nigri

Aflatoxin and ochratoxin are among the most resistant and severe toxins produced by Aspergillus spp. The aim of this study was an evaluation of eliminatory effects of cold argon plasma jet on aflatoxin B1. Sampling of wheat, corn, oatmeal, flour and rice products from northern cities of Iran was carried out. The fungal species were cultured on CHAPK medium and next to sabouraud dextrose broth + malt extract (SB + ME) and also SB + yeast extract (SB + YE) media to obtain aflatoxin B1. The ELISA test was conducted to measure the aflatoxin level. The mean initial concentration of the aflatoxin from charts analysis in the SB +ME medium was 16.106 μg / kg (10.4, 8.32 and 7.55 μg / kg at 30, 60 and 360 sec, respectively), and in the SB +YE medium from 23.699 μg / kg (12.82, 9.93 and 9.54 μg / kg, respectively), at the same time. Furthermore, the mean concentrations of aflatoxin B1 by tables analysis in the SB+ ME medium changed from 20.02 μg / kg to 6.87, 10.46 and 7.55 μg / kg, at 30, 60 and 360 sec, respectively, and in the medium SB +YE from 28.85 μg / kg reached 6.56.6, 8.43 and 7.02 μg / kg, respectively, at the same time. In this study, the change or decrease in the concentration of aflatoxin B1, from Lin/Log and Log/Lin analyses of charts was significant (p&lt;0.05) at 60 s and 360 s of application of the cold argon plasma jet in both media. The cold plasma as a new technology in various fields of food and agriculture can provide effective and suitable solutions in order to promote the goals of food industry, especially in the areas of mycotoxin elimination.

Aggregation of lactic acid in cold rare-gas matrices and the link to solution: a matrix isolation-vibrational circular dichroism study.

The matrix isolation (MI) technique has been utilized with vibrational circular dichroism (VCD) spectroscopy to obtain MI-VCD spectra of lactic acid (LA) in cold argon matrices, in addition to their MI-IR spectra. The experiments have been done at three different deposition temperatures (10 K, 16 K and 24 K) under different Ar flow rates so that different degrees of LA self-aggregation occur. The structural and spectral investigations of the LA monomer and the larger (LA)2,3,4 aggregates have been undertaken at three levels of theory (B3LYP/6-311++G(2d,p), B3LYP-D3BJ/6-311++G(2d,p) and B3LYP-D3BJ/def2-TZVPD) to evaluate the effects of dispersion correction and basis sets on optimized structures, relative conformer energies, and IR/VCD spectral features. Interestingly, the relative conformer energies vary considerably with and without dispersion correction, especially when the molecule gets larger and when it is placed in solution. Such uncertainties in the relative energies and in the vibrational band positions and IR/VCD intensities highlight the challenges in interpreting experimental spectroscopic data, especially those obtained in solution. With the narrow MI-IR band width and highly characteristic MI-VCD spectral features and the trend observed at three temperatures, we have been able to correlate the spectral features confidently to those of the LA monomer and the larger (LA)2,3,4 aggregates, with the aid of theoretical modeling. Finally, by noting the similarity of MI-IR and especially MI-VCD features obtained at 24 K with those of the 0.2 M solution, and with the aid of spectral simulation at the B3LYP-D3BJ/def2-TZVPD level, a composition of LA aggregates dominated by the LA tetramer and trimer has been identified. This conclusion differs from the previous reports where the LA dimer was identified as the main species at even higher concentration in CDCl3. The present work showcases the power of MI-VCD spectroscopy in aiding solution spectral assignment and in providing insight into the complex self-aggregation behavior of LA in solution.

Surface conditioning with cold argon plasma and its effect on the osseointegration of dental implants in miniature pigs

PurposeSuccessful implant therapy is based on fast, safe, and predictable osseointegration. Several surface modifications have been introduced to improve the bone-to-implant interaction. This in vivo study evaluates the impact of plasma surface conditioning on early wound healing and osseointegration. Materials and methodsA total of 16 dental implants with a sand-blasted and acid-etched surface were conditioned with cold atmospheric plasma prior to insertion in the frontal bone of four miniature pigs. Sequential fluorescence labeling was administered to label bone metabolism, and after 8 weeks, bone blocks were harvested for radiological, histological, and histomorphometrical evaluation. ResultsThe plasma conditioning had no impact on the morphology of the implant surface. The bone-to-implant contact ratio was 90.4% and 86.5%, the interthread bone density 72.5% and 63.4%, and the periimplant bone density 60.5% and 61.1%, in the plasma conditioned group and control group, respectively. Concentric bands of fluorescence enrichment indicated a chronological and homogenous mineralization of newly formed bone. No unwanted periimplant side effects were detected. ConclusionThe increased parameters for osseointegration in this in vivo study merit further investigation in prospective clinical trials.

Comparison of polyhexanide, cold atmospheric plasma and saline in the treatment of canine bite wounds.

To compare the efficacy of polyhexanide, cold argon plasma and saline in reducing bacterial bio-burden in dog bite wounds. Prospective blinded randomised clinical trial. Dogs were randomly assigned to one of the treatment groups by lottery and bacterial cultures obtained before and after treatment were compared. Bite wounds were surgically debrided and treated with polyhexanide, cold argon plasma or saline lavage. All wounds were cultured three times: directly after debridement, directly after prelavage with 2 mL/cm2 (saline in the saline and cold argon plasma group, or polyhexanide) and following the definitive lavage. Data were analysed using a generalised linear model for ordinal data. A total of 85 dogs were enrolled in this study (polyhexanide n=29, cold argon plasma n=28, saline n=28). Positive bacterial culture results after debridement were obtained in 53/85 (62.3%) wounds. Polyhexanide and saline lavage significantly reduced the bio-burden, while cold argon plasma treatment did not. This effect was evident after prelavage when polyhexanide performed significantly better than saline and cold argon plasma as well as after final treatment. No significant differences were detected after prelavage or main treatment between saline and cold argon plasma. Polyhexanide lavage achieved the best immediate and ultimate decontamination of bite wounds.

Development of surface barrier detectors of low leakage current employing argon cold plasma assisted silicon surface cleaning prior to detector fabrication

The performance of silicon surface barrier detectors was improved by atmospheric pressure argon cold plasma assisted surface cleaning compared to routine cleaning using organic solvents, prior to edge protection using epoxy, then followed by metallization. The silicon wafers' surfaces were exposed to plasma etching, after lapping and chemical etching. The plasma cleaning conditions were optimized with respect to feed gas composition, flow rates and exposure time. Various Au/n-Si surface barrier detectors fabricated thereof were characterized by measuring forward and reverse Current-voltage (I-V) characteristics and alpha energy spectra obtained on exposure to α-particles. The variation of alpha energy resolution with applied reverse bias voltage for each detector was also studied. The results reveal that the leakage current of the new detectors treated with cold plasma formed by a mixture of Argon and Air (90% Argon and 10% Air) was substantially lower than that of surface barrier detectors fabricated following conventional methods.

Laminar and turbulent flow modes of cold atmospheric pressure argon plasma jet

Laminar and turbulent flow modes of a cold atmospheric pressure argon plasma jet are investigated in this work. The effects of the gas flow rate, applied voltage, and frequency on each plasma mode and on intermodal transitions are characterized using photographic, electrical, and spectroscopic techniques. Increasing the gas flow rate increases the plasma jet length in the laminar mode. Upon transition to the turbulent mode, increasing the gas flow rate leads to a decrease in the plasma jet length. The flow rate at which the jet transitions from laminar to turbulent increases with the applied voltage. The presence of nitric oxide (NO) radicals is indicated by the emission spectra of the turbulent plasmas only, while excited Ar, N2, OH, and O excited species are produced in both laminar and turbulent modes. With no distinctive behavior observed upon transition between the two operating modes, the power consumption was found to be insensitive to gas flow rate variation, while the energy density was found to decrease exponentially with the gas flow rate. Rotational and vibrational temperature measurements of the two plasma modes indicated that they are of the non-thermal equilibrium plasma type. Since they offer NO radicals while maintaining the benefits of the laminar plasma jet, the turbulent plasma jet is more useful than its laminar counterpart in biomedical applications.

Argon Cold Plasma–A Novel Tool to Treat Therapy-resistant Corneal Infections

To test whether therapy-resistant corneal infections can be successfully treated with argon cold plasma to reduce or eliminate pathogen microorganisms without affecting corneal cell viability. First-in-human case series and experimental study. Cold plasma effects on viability of primary human corneal limbal epithelial cells were studied using exposure times from 0.5 to 10minutes (metabolic activity, oxidative stress, apoptosis). Disinfective potential of cold plasma was tested against common pathogens (Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Pseudomonas aeruginosa, and Candida albicans) on culture medium and evaluated by counting colony-forming units and optical density measurements, as well as against S aureus in a human cornea infection model. Additionally, in a first-in-human trial 4 patients with therapy-resistant corneal ulcers were treated to evaluate the clinical potential of cold plasma. Cells treated for 0.5-5minutes completely recovered within 24 hours without changes in morphology; only 10-minute treatment impaired the cells permanently. No evident oxidative stress, apoptosis, or damage to the corneal structure could be found. All pathogens were susceptible to cold plasma treatments, with different levels of sensitivity. The condition of all 4 patients significantly improved after cold plasma treatment combined with antibiotic therapy. Our results indicate that argon cold plasma treatment reduces or eliminates common pathogens without impairing corneal epithelial cells invitro, exvivo, and in direct application on patients' eyes. We conclude that argon cold plasma therapy offers a potential supplement or alternative therapy for therapy-resistant corneal infections. A larger, comparative study is necessary to further confirm these findings.

Development of a new quaternary alloy Ti–25Ta–25Nb–3Sn for biomedical applications

Metallic biomaterials have been used for biomedical applications, such as cardiovascular, orthopaedics and orthodontics, due to excellent properties. In this study, the mechanical properties and corrosion resistance of new quaternary alloy Ti25Ta25Nb3Sn were evaluated. Alloys were processing in arc melting furnace with argon atmosphere and cold worked by rotary swaging. Alloy microstructure, crystalline phases and mechanical properties such as Young’s modulus, yield strength and tensile strength were evaluated. Corrosion resistance was investigated in fluoride solution by electrochemical polarization and biocompatibility with human dermal fibroblasts were also evaluated. In our study, for quaternary alloy Ti25Ta25Nb3Sn the stabilization of beta phase was maintained. It was observed that the elastic modulus of Ti25Ta25Nb3Sn (65 GPa) was lower than CP Ti (105 GPa) and Ti6Al4V (110 GPa) and slightly higher than Ti25Ta25Nb (55 GPa) alloy. The addition of Sn suppressed the double yielding verified on ternary alloy Ti25Ta25Nb. Electrochemical studies showed that stable passive oxide film was formed on the Ti25Ta25Nb3Sn surface and an increase of HDF adhesion and proliferation on alloy surface, indicating that the alloy is non-cytotoxic may provide a favorable material for biomedical applications. Results obtained showed that Ti25Ta25Nb3Sn alloy is indicated for biomedical applications.

The surface modification by cold argon plasma jet on the biodegradable films from Perna Viridis shell

The present study aims to characterizing the properties of chitosan film (biodegradable films) with prepared from the Perna Viridis Shell, and investigate the effect of an atmospheric pressure plasma jets (APPJs) in pure argon used to modify the surface of chitosan film. The properties have also been discussed in detail with X-Ray Diffraction (XRD), Energy Dispersive X-rays spectrometer (EDXRF) and scanning electron microscope (SEM). The XRD and SEM were explaining the crystalline and morphology properties, while the chemical composition in the chitosan film used EDXRF. The result of the XRD pattern indicated the chitosan film, can be observed the mixture phase between chitosan hydriodide phase and calcium acetate hydrate. After that, the surface modification by the APPJs exhibit the water contact angle decreased as the duration of the plasma treatment. Another that, the SEM micrograph exhibited a significant different in surface topography of the film after plasma treatment and increased the chitosan film have surface roughness.

Innovative sterilization technology - bacterial inactivation by cold argon plasma

Non-thermal (cold) plasma is subject of intensive scientific interest as an alternative sterilization technique for advanced control of microbial quality and safety in food biotechnology. The cold plasma is a flow of weakly ionized gas at atmospheric pressure that includes radicals, H2O2, O3, ultraviolet radiation, charged particles, exited metastable atoms, electric fields. One of the major benefits of plasma-based technologies is the synergy between the strong effects of these highly active components that provides a high bactericidal efficiency at low costs, time-saving and non-toxicity. The aim of this study is to assess the bactericidal effect of cold argon plasma in liquids and surfaces, contaminated with Gram-negative and Gram-positive spore-forming bacteria. The used plasma source is surface-wave-sustained discharge (SWD) operating at 2.45 GHz in argon (plasma torch) produced by an electromagnetic wave launcher surfatron type. The bactericidal effect was studied by direct contact treatment of contaminated liquids and agar plates with Pseudomonas aureofaciens AP-9 and Brevibacillus laterosporus BT-271. The results show that the cold argon plasma is able to inactivate bacteria at short exposure time (under 1 min). The clear sterilization zones on treated surfaces with diameter depending on exposure time and initial bacterial density were obtained. In bacteria-contaminated liquids the partial disinfection was observed at least. The potential of plasma based technologies as innovative sterilization approach is high and can be used for various purposes related to microbial control and food safety.