AVS 51st International Symposium
    Biomaterial Interfaces Monday Sessions
       Session BI-MoP

Paper BI-MoP37
Plasma Sterilisation of Thermalabile Materials

Monday, November 15, 2004, 5:00 pm, Room Exhibit Hall B

Session: Poster Session
Presenter: H. Halfmann, Ruhr-Universitaet Bochum, Germany
Authors: H. Halfmann, Ruhr-Universitaet Bochum, Germany
M. Schulze, Ruhr-Universitaet Bochum, Germany
M. Czichy, Ruhr-Universitaet Bochum, Germany
P. Awakowicz, Ruhr-Universitaet Bochum, Germany
Correspondent: Click to Email
In recent years plasma sterilisation has been developed to a certain degree that makes the corresponding results reliable. Due to the advantages of plasma sterilisation great efforts in world wide investigations are made. The dry and cold process without toxic ingredients is the large benefit of the plasma sterilisation. At the institute of Electrical Engineering and Plasma Technology (AEPT) investigations on plasma sterilisation of medical implants and PET are performed. The experiments are focused on spores and germs which are important in medical, pharmaceutical and food branches. Additionally the influence of the plasma treatment on pyrogens is examined. With the sterilisation and surface modification our attention is on medical implants made of titan, UHMWPE and degradable polylactide. Conventional procedures have several disadvantages besides the long total treatment time. The plasma process reduces germs by 6 decades in a total treatment time of less than 2 minutes. Unlike common sterilisation processes the procedure is also able to reduce pyrogens. In addition to the sterilisation the surface of UHMWPE is hardened by the plasma process. Gel content measurements indicate the improvement of abrasion resistance while the bulk material is not modified. An increasing part of non-carbonated and non-acidic beverages have been bottled in PET. For sensitive products aseptic filling must be guaranteed. A plasma process prepares bottles for aseptic filling within seconds without toxic residua. To improve the shelf-live of oxygen-sensitive soft drinks a diffusion barrier made of a SiO@sub x@ layer can be deposited on the inner side of a PET bottle in a second process step. The whole process may be performed on a plasma line microwave reactor and is done in less than 10 seconds. The future work is aimed at unterstanding the mechanisms of sterilisation in the plasma with regard to ions, neutrals and radicals to optimise the procedure.