The Application of Plasma Sterilization for SUDs

1. The Application of Plasma Sterilization for SUDs A novel Non-thermal Atmospheric Dielectric Barrier Discharge Ribbon Electrode MEM-031 Shawn Anderson William Borrell John Mattero Joseph Neal Royston Rodrigues Advisors: Dr. Y. Cho Dr. A. Fridman

2. The problem: Preventing pathogenic contamination • Bacteria are everywhere and surface contamination is practically unavoidable • Contaminated medical and surgical instruments can easily transmit bacteria which, leading to potentially fatal infections • Sterilization inactivates potentially harmful microorganisms +

3. Sterilization and Current Techniques • Electron Beam • Gamma Radiation • Ethylene Oxide • Thermal (Autoclaving) • Most popular • High temperatures and pressures denature proteins and kill bacteria

4. The problem with current sterilization techniques • Electron Beam • Very expensive, dagerous • Gamma Radiation • Ethylene Oxide • Long duty cycles • Toxic residues absorbed by materials • Thermal (Autoclaving) • Not applicable for heat sensitive materials • Some strains of bacteria are unaffected • Temperatures of 121°C are energy expensive and dangerous

5. Advantages of Plasma Sterilization • Faster • Experimentations of different treatment times shows a 6 log reduction in less than ten minutes • Safe for all surfaces and materials • More energy efficient • Power ratings less than that of a light bulb • Relatively Nontoxic • The only toxic byproduct is ozone, which can easily be removed • Inactivates the hardiest of bacteria • The inherent mechanisms of plasma sterilization are almost impossible for bacteria to adapt to*

6. What is Plasma • Plasma – 4th state of matter • Ionized gas • Depending on how energy provided can be thermal or non-thermal (cold) plasma • Dielectric Barrier Discharge (DBD) • Dielectric barrier discharge • Created when high voltage is applied6 • Charge builds up on surface • Electrons that enter region form electron avalanche • Advantage as produces high energy electrons directly

8. How do general plasmas sterilize • Inactivation kinetics are not absolute • Current theories include • UV radiation • UV radiation can cause DNA damage or surface modifications which activates cell death mechanisms • Heat • Streamers produce temperatures of up to 1eV or 2.3x105 K • Charged particles • Electrons and positively/negatively charge ions • Direct and indirect effects of Reactive species • O, O2, O3, OH, NO, NO2compromise bacterial cell wall components

9. How does DBD plasma sterilize • Heat inactivation is negligible • UV inactivation is negligible • Leaves reactive oxygen species and charged particles as the primary sterilants • Rate of ionization • keo - Collision Rate coefficient of electrons and neutral atoms, • I – activation energy • Te – electron temperature e + O2 O + O + e O + O2 + M  O3 + M e + H2O  H + OH + e

10. DBD Plasma Sterilization 0.5 0.5 0 0 2.5 μm μm 0 0 Horizontal distance: 1.074 μm Vertical Distance: 463.45 nm Horizontal distance: 531.46 nm Vertical Distance: 108.39 nm

13. Specifications of the Box

14. Specs of the Electrode

15. Plasma Characterization • Talk about plasma characterization • talk about power source characterization (get data from posters)

16. Power Source Characterization

17. EXPERIMENTS • What can our box do????

18. PROTOCOL

19. DEMO

20. Production

21. REPROCESSING SINGLE-USE MEDICAL DEVICES • Single-Use Medical Devices (SUD) • Scalpel handles, forceps, scissors, speculums, etc. • Defined as used, open, or expired • FDA and MDUFMA • Validated sterilization procedures must accompany 510K submissions • Requires similar standards as OEMs

22. WHY REPROCESS • If 1-2% of all SUDs were reprocessed, savings of $1,000,000,000/yr • Up to 50% savings when reprocessing once • 10 Million tons of waste diverted from landfills each year • Increased reliability

23. COMPETITIVE ADVANTAGES • Size • Scalable to large container size • Possible conveyor belt mechanism with automated sterilization • Efficacy • Proven to kill D. radiodurans, E. coli • Short duration exposure times • 30sec to 10hrs • Safety • Runs off 110V wall power supply • Non-thermal plasma safe to touch

24. SENIOR DESIGN BUDGET

25. Industrial Budget

26. Dr. Young Cho Dr. Alexander Fridman Dr. Greg Fridman Moogega Cooper Drexel Plasma Institute

27. REFERENCES – ADD THESE WITHIN THE PRESENTATION (CITE FIGURES) 1 http://www.myendosite.com/cms/files/July_1998_ID478.pdf • http://www.unc.edu/depts/spice/dis/ICHE-1996-Feb-p87.pdf • http://www.devicelink.com/mddi/archive/02/09/003.html • http://books.google.com/books?id=3f-kPJ17_TYC&pg=PA351&lpg=PA351&dq=plasma+sterilization+medical+devices&source=bl&ots=KkCpEv8PFZ&sig=hvTIRX2UtewsEEo0qgKqcfs8ugQ&hl=en&ei=7P2tSfHpCIiSngeElojDBg&sa=X&oi=book_result&resnum=7&ct=result • http://www.swri.org/3pubs/ttoday/Spring96/ttoday2.htm • http://www.gregfridman.com/publications/documents/STAR-RyanRobinson.pdf • Laroussi, Mounir. "Low Temperature Plasma-Based Sterilization: Overview and State-of-the-Art." Plasma Processes and Polymers 2 (2005): 391-400. • Fridman, Gregory, Peter I. Lelkes, and Kenneth Barbee. "Physical and Biological Mechanisms of Plasma Interaction with Living Tissue." Prepublication (2007).