FROM THE IDEA TO THE PROTOTYPE Plasma Life-Science Applications R. Brandenburg, Th. von Woedtke, K.-D. Weltmann Leibniz Institute for Plasma Science and Technology Greifswald, Germany With contributions from partner and colleagues in the network project: 2 H.M. Mott-Smith; Nature, 233, p. 219, (1971) „ ... the discharge acted as a sort of substratum carrying particles of special kinds […] This reminds him of the way blood plasma carries around red and white corpuscles and germs. So he proposed to call our ‚uniform discharge‘ a ‚plasma‘. Of course we all agreed.“ First use of the term „plasma“: Langmuir (1928) Langmuir‘s colleague Harold M. Mott-Smith remembers in 1971: Credit:NicoleRager-Fuller,NSF Irving Langmuir (1881–1957) at General Electric Laboratory (1948) Plasma for biomedical applications Surface modification Biocompatibility Antifouling Microfluidics Cell culture systems Plasma Medicine “classical”: surgical applications (coagulation or ablation of tissue) new: wound and tissue treatment (“plasma can heal”) © INP Erbe Elektromedizin Bio-Decontamination/Sterilization Inactivation of pathogens and microorganisms on sensitive products (disinfection, sterilization) as well as gases and liquids Protection against biological warfare agents © INP 4 Plasma life science 5 Implants bone implants (joints, teeth) tendons and ligaments vascular grafts stents heart valves Therapy devices catheters dialysis devices pacemakers Disposables cell culture dishes DNA chips biosensors high throughput screening systems Vacuum Plasma Spraying of titanium DOT GmbH DOT GmbH Corrosion protection by PVD Functionalized titer plates Plasma in use Surface modification for biomedical applications 12 Plasma life science 13 Decontamination / Sterilization: some definitions Decontamination: Removal of dangerous contaminations CBNR (Chemical, Biological, Radiological, Nuclear) includes prions, pyrogens, viruses, chemical contaminations etc. Antimicrobial Treatment (R. Koch, 1881): Inactivation of microorganisms with the aim to reduce/avoid infections Disinfection: to put dead or living material in a situation, that it is no longer able to contaminate Practical advise: reduction of infective micro organisms including viruses Sterilization: „Sterility is the absence of viable micro organisms.“ (Ph. Eur., USP) Sterility Assurance Level SAL= 10-6: not more than one viable microorganism in one million sterilized items of the final product Robert Koch (1843-1910) 14 Alternatives for heat sensitive products Ionising radiation sterilisation (gamma radiation – radioisotopic source, electron beam – electron accelerator): 25 kGy Gas sterilisation (ethylene oxide) LTSF - Low-temperature steam/formaldehyde Chemical wet sterilisation (glutaraldehyde, peracetic acid, hydrogen peroxide) VHP - Vapor-phase hydrogen peroxide: hydrogen peroxide, peracetic acid UV irradiation (254 nm) Sterilisation/decontamination procedures Standard and reference procedures Steam sterilisation (heating in an autoclave): 121°C, 2 bar, 15 min Dry heat sterilisation : ≥ 160°C, ≥ 2 h 16 Specific antimicrobial effects of plasmas Antimicrobial effect of plasmas proven in many experiments with different plasma sources but effects very specific + + Plasma parameters, components Lethality of micro org. e.g. UV sensitivity/resitivity Preparation of samples e.g. arrangement of micro org. MiBi procedures e.g. detection limits, artefacts 17 Biologically active components of plasmas (V)UV-radiation damage of DNA cell wall damage by photo-induced erosion Global Effects Temperature surface heating Electric Fields electroporation Radicals and Chemical products cell wall damage by reactive etching (O, O2*) DNA damage by oxidation oxidation of proteins (O) oxidation of lipid bilayers (fatty acids) (OH) O3 cell respiration natural signal stimulation (NO) Charged particles (ions) electrostatic pressure by accumulating charge carriers on membrane charge lysis of cells Plasma-cell interactions: various hypotheses D. Dobrynin, G. Fridman, G. Friedman, A. Fridman, Physical and biological mechnaisms of direct plasma interaction with living tissue. New J. Phys 11 (2009) 115020 G. Fridman et al., Plasma Chem. Plasma Process. 26 (2006) 425 19Philip et al., IEEE Trans. Plasma Sci. 30 (2002) 1429 Low-pressure afterglow plasma, 915 MHz/2.45 GHz, 100-200 W, N2-O2 gas mixtures; spores dried on a polystyrene surface UV radiation + Erosion caused by reactive species Low-pressure plasma 19 23R. Brandenburg, J. Ehlbeck, M. Stieber, Th. von Woedtke, J. Zeymer, O. Schlüter, K.-D. Weltmann, Contrib. Plasma Phys. 47 (2007) 72-79 PE strip 2cm Atmospheric pressure RF Argon Plasma jet (27 MHz, 10…60 W) Bacillus atrophaeus spores, dried on PE strips; Separation of plasma compounds by quartz window or hot gas flow Direct plasma treatment quartz glass plate PE strip UV only PE strip Heated air flow Q=20 slm T=80-90°C Heat only Atmospheric-pressure plasma 24 R. Brandenburg, J. Ehlbeck, M. Stieber, Th. von Woedtke, J. Zeymer, O. Schlüter, K.-D. Weltmann, Contrib. Plasma Phys. 47 (2007) 72-79 Treatment time (min) 0 1 2 3 4 5 6 7 8 9 10 11 CFU/strip 101 102 103 104 105 106 107 detection limit plasma UV only Hot air only (Median, error bars: Min./Max.; je n=5) Atmospheric pressure RF Argon Plasma jet (27 MHz, 10…60 W) Bacillus atrophaeus spores, dried on PE strips Separation of plasma compounds by quartz window or hot gas flow Atmospheric-pressure plasma 28 Indirect surface DBD on air: influence of humidity B. Atrophaeus spores dried on PE strips M. Hähnel, Th. von Woedtke, K.-D. Weltmann, Plasma Process. Polym. 7 (2009) 244-249 Influence of humidity 29 Specific antimicrobial effects of plasmas Antimicrobial effect of plasmas proven in many experiments with different plasma sources but effects very specific + + Plasma parameters, components Lethality of micro org. e.g. UV sensitivity/resitivity Preparation of samples e.g. arrangement of micro org. MiBi procedures e.g. detection limits, artefacts 30 Quantifiable effectivity of an antimicrobial process depends on nature and resistance of the microorganisms used. Use of test microorganisms with maximum resistance against the process to be examined. Bacterial spores vs. vegetative microorganisms http://micro.magnet.fsu.ed u/cells/procaryotes/images /procaryote.jpg # Resistance of microorganisms Quantification of sterilisation effects http://www.micro.cornell. edu/cals/micro/research/l abs/angert- lab/images/endospore.jpg Specific antimicrobial effects of plasmas Different resistance against external factors: heat, UV, chemicals, plasma components, … High resistance against external factors: Bioindicators for sterilization control Size: 0.1-1 µm 32 Plasma treatment time (min) 0 2 4 6 8 10 cfu/sample 101 102 103 104 105 106 107 Bacillus atrophaeus spores Escherichia coli Staphylococcus aureus detection limit Rf-driven Plasma Jet, 20 W, Argon 20 slm Microorganism resistance 33 Specific antimicrobial effects of plasmas Antimicrobial effect of plasmas proven in many experiments with different plasma sources but effects very specific + + Plasma parameters, components Lethality of micro org. e.g. UV sensitivity/resitivity Preparation of samples e.g. arrangement of micro org. MiBi procedures e.g. detection limits, artefacts 34 Bacterial load Spray: 2 104 MO/cm2 Spot: 1.4 107 MO/cm2 ... more or less single spores on surface ... stacked spores (several layers) F. Rossi et al., Plasma Process. Polym. 3 (2006) 431; J. Wunderlich et al. ISPC 2003 Rossi et al. Identical plasma treatment leads to different lethal effects! 36 Substrate material Low-pressure glow-discharge oxygen RF plasma, 27.12 MHz, 300 W, continuous and pulse mode (5 s on, 25 s off) performance; forced-air cooled discharge vessel; B. subtilis spores dried on glass and Al-foil Cvelbar et al., J. Phys. D: Appl. Phys. 39 (2006) 3487 Different substrate heating caused by surface recombination of O-atoms Combined effects of temperature and O-based atom-by-atom etching of bacteria 37 Specific antimicrobial effects of plasmas Antimicrobial effect of plasmas proven in many experiments with different plasma sources but effects very specific + + Plasma parameters, components Lethality of micro org. e.g. UV sensitivity/resitivity Preparation of samples e.g. arrangement of micro org. MiBi procedures e.g. detection limits, artefacts 38 Ph. Eur. [USP, JP]: „Sterility is the absence of viable micro-organisms.“ Plasma “sterilisation“ What does it mean: sterility/sterilisation? Sterility Assurance Level - SAL 10-6 denotes a probability of not more than one viable micro-organism in 1 × 106 sterilised items Problem: Proof of sterility assurance 40 Exponential microorganism inactivation kinetics Treatment intensity [x] (time, dose, concentration, ...) Numberofviablemicro-organisms[N] 0 200000 400000 600000 800000 1000000 Numberofviablemicro-organisms[N] 10-6 10-5 10-4 10-3 10-2 10-1 100 101 102 103 104 105 106 Treatment intensity [x] (time, dose, concentration, ...) Microbiological tests general assumption! 41 Direct cell counting (spread-plate method) Spread on culture medium (agar) and incubation Dilution series with 100 µl aliqout Agitation in 10 ml 0.9 % NaCl Treated test objects (source: SÜßMUTH/EBERSPÄCHER/HAAG 1987) Detection limit: 101-102 CFU/obj. ... applied if viable micro organisms present on all test objects saline solution 42 Membrane filtration Agitation in 10 ml 0.9 % NaCl Membrane filtration Filter on culture medium (agar) and incubation Detection limit: 1 cfu/obj. ... applied when less than a few hundred viable micro organisms on test object expected Treated test objects saline solution 43 Fraction negative method Detection limit: 10-1 ... 10-2 cfu/obj. ... applied if test objects both with and without viable micro organisms expected Incubation in nutrient solution (broth) turbidity of broth gives evidence for microbial growth m = - ln(n0/n) m ... mean number of survivors per test object n0 ... number of test objects without viable micro organisms n ... number of identically treated test objects n Treated test objects nutrient solution 44 0 2 4 6 8 10 12 14 16 Numberofviablemicroorganisms[N] 10-6 10-5 10-4 10-3 10-2 10-1 100 101 102 103 104 105 106 Extrapolation Fraction negative method Direct cell counting Treatment intensity [X] Limits: „Sterility is the absence of viable microorganisms.“ → Sterility Assurance Level SAL= 10-6 (Ph. Eur.) → practical proof: RF ≥ 6 lg Ideal: linear inactivation kinetics ↓ continuous effectivity Real: discontinuous effectivity Plasma-“Sterilisation“ 45 Plasma treatment time (min) 0 2 4 6 8 10 cfu/sample 101 102 103 104 105 106 107 Bacillus atrophaeus spores Escherichia coli Staphylococcus aureus detection limit Real inactivation kinetics PE strip 2cm Rf-driven Plasma Jet, 20 W, Argon 20 slm 48 Other non-thermal treatments 2% 3 % 4% Glutaraldehyde treatment time [h] 0 1 2 3 4 5 meannumberofviablespores pertestunit 10-2 10-1 100 101 102 103 104 105 106 107 2% 3 % 4% UV irradiation time [s] 0 5 10 15 20 25 30 Numberof colonyformingunits(cfu)perml 100 101 102 103 104 105 106 107 108 109 UV irradiation of B. atrophaeus spore suspensuions Direct cell counting mean ± SD n=10 per data point Treatment of B. atrophaeus spore strips by glutaraldehyde solution Fraction negative method m = - ln (n0/n) n=20 per data point von Woedtke & Jülich, Pharmazie 56 (2001) 561 von Woedtke et al., Biosens. Bioelectron. 17 (2002) 373 von Woedtke et al., J. Hosp. Infect. 55 (2003) 204 49 Heat-based processes • global excited energy state • lethal changes of micro-organism structures resulting from a constant and ubiquitous activity ⇒⇒⇒⇒ inactivation kinetics independent from number of targets →→→→ extrapolation possible Non-thermal processes • discrete energy quanta or reactive molecules • lethal changes of micro-organism structures resulting from „hits“ at susceptible target structures ⇒⇒⇒⇒ inactivation kinetics strongly dependent from number of targets →→→→ extrapolation problematic Theory of antimicrobial activity 50 use of most resistant test micro-organisms documentation of inactivation kinetics over ~ 5 log first of all in the range of low contamination rates (down to 10-2 if possible) Resulting practical demands for plasma „sterilization“ Proof of antimicrobial efficacy on the highest experimentally accessible level Plasma treatment time (min) 0 1 2 3 4 5 6 7 8 9 10 11 cfu/sample 101 102 103 104 105 106 107 Bacillus atrophaeus spores 51 Sterilisation and decontamination using low-pressure plasmas 52 Commercially available “plasma sterilization”: Sterrad® Sterilization Systems (Advanced Sterilization Products, Ethicon Inc., Johnson & Johnson) Sterrad® 100S 1 2 3 4 5 Wrapped Samples Trays Plasma Region Matching Network Perforated Powered Electrode 6 7 8 9 To Vacuum Pump Vacuum Chamber (grounded) Pressure Gauge H2O2 Vapour Injection Port Lerouge et al., Plasmas and Polymers 6 (2001) 175; Moisan et al., Int. J. Pharm. 226 (2001) 1; http://www.aspjj.com Sterilisation and decontamination using low-pressure plasmas 53 Commercially available “plasma sterilization”: Sterrad® Sterilization Systems (Advanced Sterilization Products, Ethicon Inc., Johnson & Johnson) Sterrad® 100S 1 2 3 4 5 Wrapped Samples Trays Plasma Region Matching Network Perforated Powered Electrode 6 7 8 9 To Vacuum Pump Vacuum Chamber (grounded) Pressure Gauge H2O2 Vapour Injection Port Lerouge et al., Plasmas and Polymers 6 (2001) 175; Moisan et al., Int. J. Pharm. 226 (2001) 1; http://www.aspjj.com inherent efficacy is above all due to hydrogen peroxide plasma phase: residue detoxifying process Krebs et al., Int J. Pharm. 160 (1998) 75 Sterilisation and decontamination using low-pressure plasmas 54 Commercially available atmosperic pressure plasma system: TipChargerTM (Cerionx Inc., Rxton, PA, USA) www.cerionx.com low-temperature ('cold') atmospheric pressure plasma (DBD) used to clean and sterilize pipet tips by removing organic substances from treated surfaces. Sterilisation and decontamination using atmospheric pressure plasmas 55 additional features of atmospheric pressure plasma: contracted plasmas effects are limited locally effects can be located exactly Plasma-“Sterilisation“ 56 INP INP 300 mm 150 µm gap Chances of atmospheric pressure plasmas: - customisation according to special product characteristics, demands, geometries Plasma-“Sterilisation“ INP www.endoplas.de 5757 ‘Sterilization’ of heat sensitive products Medical devices (instruments, implants) Pharmaceutical packagings Pharmaceutical preparations http://www.nanobionet.org INP INP INP INP Vanguard AG INP INP/dpa INP INP INP INP Plasma technology for biological decontamination 2004: Beginn der Verbundprojekts „PLASMOSE – Plasmagestützte Oberflächenmodifizierung mittels modularer selektiver Plasmaquellen“ 58 Endoscopes as medical instruments control unit light and video connectors distal end tubular device 4 mm light guidecamera light guide tubular device Plasma inside closed packaging - Adapted Dielectric Barrier Discharge (DBE) Plasma ignited inside of the packaging - Prooven by FTIR-Gasanalyses within packaging 65 Chances and perspectives: 1. Antimicrobial effectivity of atmospheric pressure plasmas against a broad spectrum of microorganisms was proved in many cases 3. Several possibilities to integrate atmospheric pressure plasma sources as part of special product and/or process-related master plans of (micro-) biological decontamination, above all for manufaacturing and (re-)processing of medical devices 4. Plasma treatment of liquids expandable: microbiological decontamination Investigation of biological plasma effects 2. Ubiquitous applicable sterilization procedures based on atmospheric pressure plasma are hardly to realize 5. Huge potential in the field of in vivo antiseptics → plasma medicine Sterilisation and decontamination using atmospheric pressure plasmas Plasma life science „Recent demonstrations of plasma technology in the treatment of living cells, tissues, and organs are creating a new field at the intersection of plasma science and technology with biology and medicine – Plasma Medicine.“ M. Laroussi & A. Fridman, Editorial Plasma Process. Polym. 5 (2008) 501 Plasma medicine 67 68 ‘Violet Rays’ or ‘Violet Wands’ & the Zeileis method www.electrotherapymuseum.com Antique 'quack' medical devices claimed to be useful in electrotherapy The Zeileis method (1912) – HV treatment 1 H. BURGER: The Doctor, the Quack, and the Appetite of the Public for Magic in Medicine,Proceedings of the Royal Society of Medicine, 1.11.1933 [1] 2 Zeileis-Institut, Valentin-Zeileis-Straße 33, A-4713 Gallspac „Conventional“ surgical plasma applications Zenker M, GMS Krankenhaushyg Interdiszip 3 (2008) Doc15; Raiser & Zenker, J. Phys. D: Appl. Phys. 39 (2006) 3520 Argon Plasma Coagulation (APC) ERBE Elektromedizin GmbH,Tübingen, Germany Coblation® (cold ablation) ArthroCare Corp., Synnyvale, CA,USA Stalder KR, Woloszko J, Contrib Plasma Phys 47 (2007) 64; www.arthrocareent.com/ Plasma medicine: step forward lethal plasma effects (antimicrobial; surgical) Selectivity of plasma treatment Plasma can heal! + non-lethal plasma effects Chronic wounds 4.5 to 5 million people in Germany suffer from chronic wounds i.e. ca. 5% of all stationary patients in hospitals and rehab hospitals loss quality of life for patients health economic problem: > 5 Mrd. € per year in Germany increasing problem because of ageing population e.g. pressure ulcers, venous insufficiency ulcers, diabetic/neuropathic ulcers Actual Focus: Wound Healing Wound antiseptics Chronic wounds (no healing within 8 weeks) Frequent cause: wound infections Staphylococcus aureus, Staphylococcus epidermidis Streptococcus pyrogenes, MRSA Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa anaerobians expenditure of time, adverse effects ! Conventional therapy: chemical antiseptics 74 Plasma Medicine: vision Superficial cleaning and antiseptics + Stimulation of tissue regeneration in deeper layers Integrated concept of plasma-based wound treatment Plasma-cell interactions PLASMA CELLSGAS PHASE LIQUID PHASE 76 78 Experimental Plasma Medicine Plasma sources Biological effects development adaptation diagnostics optimization, control, monitoring experimental applications Therapeutic Applications physiological liquids cells: - microorganisms - mammalian cells cell and tissue cultures: - not contaminated/infected - contaminated/infected isolated tissues/organs organisms: - animal experiments - clinical investigations in vitro in vivo 79 The bans for new methods in medicine … Non-thermal Atmospheric Pressure Plasma Sources INP Basic requirements for therapeutic applications Plasmas which ... ... operate at atmospheric pressure treatment of living objects manageability (operation at open atmospheres) ... operate stable reproducibility of treatment results reliability ... are well characterized quantitative knowledge on plasma parameters and “macroscopic” characteristics process monitoring influence by operation parameters 81 INP MPE INP TU/e MPE GREMI Lough- borough ODU Atmospheric pressure plasmas for biomedicine Plasma Nozzle Isolation Gas High voltage supply Electrode Plasma Object (Tissue) Stray capacity Drexel Cinogy Surface Discharge Volume Barrier Discharge Plasma jet K.-D. Weltmann et al., Pure Appl. Chem., Vol. 82, No. 6, (2010) From kINPen 09 to kINPen MED Simple and safe use under consideration of the excisting and known basic plasma properties Requirements according to DIN EN 60601-1 PLL-Electronic for optimal Plasmaignition Gas-flow-control, automatic shut down Timercontrol to secure a maximum dosage Burst-Mode: lower irritation by current and temperature to the surface, lower radiation output Distance holder for reproducable treatment 83 90 Adapted device for petri dishes closed confinement variable distance DBD to surface/suspension well defined and stable discharge and treatment parameters possible 60mm 95 mm Flexible discharge arrangement 94 Experimental Plasma Medicine Plasma sources Biological effects development adaptation diagnostics optimization, control, monitoring experimental applications Therapeutic Applications physiological liquids cells: - microorganisms - mammalian cells cell and tissue cultures: - not contaminated/infected - contaminated/infected isolated tissues/organs organisms: - animal experiments - clinical investigations in vitro in vivo 95 In-vitro characterization of plasma-cell interactions - General estimation of biological effectivity - Estimation of therapeutic options - Estimation of possible risk factors - Insights into reaction mechanisms 97 Neutral red uptake (NRU) assay 48 and 72 h after plasma treatment (uptake of the dye into lysosomes of vital cells → dyed cells = living cells) Influence of plasma treatment on HaCaT- RPMI Influence of plasma treatment on HaCaT- IMDM Cells in suspension →→→→ cytotoxicity Keratinocytes (HaCaT) in suspension, different media; kINPen (Ar 3.8 slm); seeding after plasma treatment Cytotoxic effects dependent on plasma treatment time and on cell culture medium Vitality(%) Vitality(%) RPMI – Rosewell Park Memorial Institute, IMDM – Iscoves Modivied Dulbeccos Media (more glucose, buffer, pyruvate) Source: University Düsseldorf Scratch assay: mechanical scratching of a 2D keratinocyte (HaCaT); detection of timedependent scratch-width reduction t24 t10t0 Adherent 2D cell cultures →→→→ scratch assay ≈≈≈≈ 3 mm Modified scratch assay K. Wende, K. Landsberg, U. Lindequist, K.-D.. Weltmann, Th. von Woedtke, IEEE Trans. Plasma Sci. 38 (2010) 2479 - 2485 Vessel with adherent cells (w/ or w/o scratch) Agarose layer (< 1mm) Cell culture medium Cell culture medium Low melting agarose HaCaT monolayer agarose with scratch HaCaT cell line with scratch petri dish microorganism Adherent 2D cell cultures →→→→ scratch assay 2D keratinocytes (HaCaT) culture (RPMI), co-cultivated with S. epidermidis; 40 s APPJ (Ar gas) Modified scratch assay: protection of cells by agarose overlay 0 0,02 0,04 0,06 0,08 0,1 0,12 0 10 20 30 40 50 time [h] scratchwidthreduction[cm] infected, plasma infected Demonstration of selective antiseptic plasma treatment K. Wende, K. Landsberg, U. Lindequist, K.-D.. Weltmann, Th. von Woedtke, IEEE Trans. Plasma Sci. 38 (2010) 2479 - 2485 103 Key results Plasma Vitro Stimulation of cell regeneration by atmospheric pressure plasma treatment No substantial structural changes of intracellular proteins (charge influenced) Dose dependent, but reversible influences on cell DNA Dose dependent emergence/generation of ROS in cells Important influence of cell culture medium on in vitro results 106C. Bender et al., Plasma Process. Polym. 7 (2010) 318–326 HET-CAM: Hens‘s Egg Test – Chorioallantoic Membrane • Standard test for eye and skin irritating potential of chemicals • Fertilized eggs, incubated for 10 d Living tissue – irritation potential Key results Plasma Cure Proof of tissue compatibility of plasma treatment in antiseptically effective doses Inactivation of bacteria without irritation of the surrounding cells/tissue Antiseptic plasma effect on human skin comparable to conventional antiseptics No influence on skin barrier function as well as on the antioxidative potential of the skin C. Bender et al., Plasma Process. Polym. 7 (2010) 318–326 A. Hammann et al., Skin Pharmacol. Physiol. 23 (2010) 328-332 109 Key results Plasma Derm Antimicrobial effect on bacteria, fungi and parasites shown Safety of application proven e.g. no skin irritation, no influence on skin barrier function, no desiccation, no change of skin pH-value, no other visible side effects Successful treatment of athlet‘s foot (Tinea pedis) Successful single treatment of inflammatory skin diseases e.g. psoriasis, acne, lichen ruber G. Daeschlein et al., Plasma Process. Polym. 7 (2010) 224-230 G. Daeschlein et al, IEEE Trans. Plasma Sci. 38 (2010) 2969-2973 G. Daeschlein et al., IEEE Trans. Plasma Sci. 39 (2011) 815-821 110 Key results Plasma Dent Successful treatment of teeth root channel in vitro Inactivation of biofilms on teeth and on dental implants Improved cell adhesion on implant surfaces Successful decontamination and coating of dental prosthesis Th. Kocher et al., Greifswald University I. Koban et al., GMS Krankenhaushyg Interdiszip. 2009;4(2):Doc09. I. Koban et al., New J. Phys. 12 (2010) 073039 I. Koban et al., Plasma Process. Polym, submitted Highlight Plasma Dent (example) Endodontics – reduction of E. feacalis 0 1 2 3 4 5 6 7 8 9 lg(KbE/ml) 1 NaCl- Spül. 2 Gaskontr. 3 Chx- Spül. 4 KINPen 08 Abtötung von E.faecalis im Wurzelkanalmodell Error Bars: 95% Confidence Interval Chlorhexidine (standard): 2 log (after 5 min. treatment) APPJ (kINPen): 3…4 log (after 1 min. treatment) Root canal model Th. Kocher et al., Greifswald University Enterococcus faecalis inactivation (Error bars: 95% confidence interval) Numberofbacteria(lgcfu/ml) NaCl rinsing Ar gas flow Chlorhexidine rinsing APPJ treatment control Persisting 4 years Plasma + Polihexanide Example German shepherd dog with chronic wound ‘Harras’, 9 years After 6.5 weeks After 11 weeks C. Bender et al. Univ. Greifswald Plasma + Polihexanide Example Labrador with chronic wound ‚Astor, 12 years 2010-12-08 2011-01-10 C. Bender et al. Univ. Greifswald Practical needs For the patient no fear no pain no delay For the doctor simple („one doctor – one knob“) robust (mm not µm) small (ambulant treatment) Outlook – „Plasma goes into hospital“ In vitro tests susceptibility toxicity selectivity Clinical tests susceptibility compatibility long-term effects Clinical needs Indications (examples) chronic inflammatory diseases acute infections auto immune diseases effectivity safety TISSUE TOLERABLE PLASMA - TTP Summary: chances & risks Chances of Tissue Tolerable Plasma: 1. Prevention and treatment of diseases (chronic wounds, skin and mucosal infectious diseases, localized tumors, keloid formation, promotion of angiogenesis, tissue ablation, hemostasis) 2. Inhibition of biofilm formation by surface treatment and by direct action on biofilms 3. Promotion of incorporation of implants into viable tissue by changing the surface (hydrophobicity, plasma steered application of antimicrobial active layers with drug delivery function) 4. Promotion of improved penetration of topically applied drugs with therapeutic outcome 5. Improved cleaning performance in the treatment process of medical devices by surface modification. Risks of plasma medicine: • A few physical, more technological and administrative • Generation of false expectations (ahead of time) • Basic scientific understanding is lacking or inadequate • Costs for implementation into practice (approval of medical devices, health insurance companies, …) The field is new, with huge chances, with significant research potential, is broad enough to promote co-operations is an opportunity for plasma technology. Summary: statement www.campus-plasmamed.de Contact INP Leibniz Institute for Plasma Science and Technology Adresse: Felix-Hausdorff-Str. 2, 17489 Greifswald Telefon: +49 - 3834 - 554 300, Fax: +49 - 3834 - 554 301 E-Mail: welcome@inp-greifswald.de, Web: www.inp-greifswald.de This study was realized within the joint research project “Campus PlasmaMed” supported by the German Federal Ministry of Education and Research (grants no. 13N9779 and 13N11188). 135