Reprocessing Single-Use Medical Devices with Plasma

1. Reprocessing Single-Use Medical Devices with Plasma 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 +

4. 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 • Validated 6-log reduction in ½ cycle Medical Device User Fee and Modernization Act of 2002 (MDUFMA) 107-250 (2002) (enacted).

5. 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 Distel, David F., and Arthur D. Goodrich. "SUD Reprocessing: The New Frontier in Supply Cost Management." Setting the Standard.

6. Competitive Advantages with Plasma • Size • Scalable to large container size • Adaptable to nearly any application • Flexible electrodes • Efficacy • Proven to kill D. radiodurans, E. coli • Short duration exposure times • 30sec to 10min • Safety • Runs off 110V wall power supply • Non-thermal plasma safe to touch

7. Sterilization and Current Techniques • Electron Beam • Gamma Radiation • Ethylene Oxide • Thermal (Autoclaving) • Most popular • High temperatures and pressures denature proteins and kill bacteria "Medical Device Sterilization: What Manufacturers Need to Know (MDDI archive, Sep 02)." Medical Device Link - The Online Information Source for the Medical Device Industry. 18 May 2009 <http://www.devicelink.com/mddi/archive/02/09/003.html>.

8. The Problem With Current Sterilization Techniques • Electron Beam • Very expensive • Gamma Radiation • Ethylene Oxide • Long duty cycles • Toxic residues absorbed by materials • Thermal (Autoclaving) • Not applicable for heat sensitive materials • 121°C • Energy expensive Ratner, BUDDY D. Biomaterials Science. New York: Academic P, 1996.

9. What is Plasma • Plasma – 4th state of matter • Ionized gas • Can be thermal or non-thermal • Depends on voltage wave form and applied current • Created when high voltage is applied Fridman, Alexander A. Plasma chemistry. Cambridge: Cambridge UP, 2008.

10. Dielectric Barrier Discharge (DBD) High Voltage Courtesy of Drexel Plasma Institute: Dr. Greg Fridman

11. i(+) NO OH e(-) i(+) O2(1Δg+) e(-) O3 i(+) i(+) O2(1Δg+) e(-) What is Our Plasma?Dielectric Barrier Discharge (DBD) Continuous wave Microsecond pulse Nanosecond pulse Courtesy of Drexel Plasma Institute: Dr. Greg Fridman

12. Electrode / Power Source Specifications • SCSI Cable • Silver wires, 1.0mm spacing • Teflon® insulation • Varying length • Surface Power Density

13. How Does DBD Plasma Sterilize? Major Bio-Active Components • Heat & UV inactivation is negligible • ROS 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 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).

14. Advantages of Plasma Sterilization • Faster • Up to a 6 log (99.99999%) 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 • Inactivates the hardiest of bacteria • The inherent mechanisms of plasma sterilization are almost impossible to develop resistance

15. Societal and Environmental Impact • Pros • Green Technology • Streamlined Reprocessing of SUDs • Sterility assurance • Cons • Ozone Production • Potential respiratory hazards • High-voltage hazards 15

16. Materials Tested • Stainless Steel • Scalpels, scissors, speculums • Aluminum • Medical device coatings • PTFE • Liners, Patches, Compression sleeves • PVC • Catheters, Drain bags, Feeding tubes • Ceramic • Joint replacements, Surgical blades

17. Experimental Setup 1

18. All samples treated and plated in triplicate with averages plotted • Wet samples – 6 log reduction in 30 sec • Dry samples – 4 log reduction in 60 sec

19. Experimental Setup 2

20. All samples treated and plated in triplicate with averages plotted • PVC – 4 log reduction in 5 min • Ceramic – 3 log reduction in 5 min

21. DEMONSTRATION

22. Our Product • One novel application for our method of sterilization • Self-contained box • Effective in facilitating sterilization of SUD’s • Highlights the versatility of the plasma technology

23. Design Constraints • DBD Plasma • Uses existing DPI power source • Used to treat conductive and non conductive surfaces • Minimal moving parts • Ribbon Electrode • Ozone filtration

24. Manufacturability • Simple design – easily reproduced on larger scale • Plasma dictates usable materials • CNC Machining • Problems with electrode could be avoided with vacuum sealing

25. Proposed vs. Actual Budget

26. Teamwork • Shawn • Validation Experiments, Lab Leader • William • Validation Experiments, Biological Research • John • Application Development, Technical Drawings • Joseph • Lead Writer, Market Research • Royston • Electrical Analysis, Power Source Characterization

27. Future Work • Complete Inactivation • Optimization of Parameters • Scale-up Experiments • Commercially viable • RNase and DNase Inactivation • Improved ribbon

28. Drexel Plasma Institute Research Team College of Engineering Dr. Alexander Fridman Ms. Moogega Cooper Dr. Gary Nirenberg Dr. Young I. Cho School of Biomedical Engineering Dr. Greg Fridman

29. Thank you! QUESTIONS?

32. SENIOR DESIGN BUDGET