Gas Plasma Sterilisation in Bulk -- COMPAMED Trade Fair


Meise GmbH, Heinz, Medizintechnik

Gas Plasma Sterilisation in Bulk

As there is Vapour- Hydogen - Plasma-Sterilisation since several years on the markets, the capacity of these machines was to low for industrial purposes. The maximum volume of the vacuum chamber was about 200 litres. This size is suitable for a small hospital, but for industrial purpose a larger chamber is desired.
In cooperation with partners from university science Heinz Meise GmbH Medizintechnik has developed a large volume Vapour-Hydrogen- Plasma-sterilization system called Steriplas 1000, a vacuum chamber volume of 1000 litres allows the sterilization of larger quantities of medical devices, e.g. 160 dialysis bloodline sets in 2.5 hours.
The process of sterilisation meets the requirements of ISO 14937, the system became a medical device and the prototype is ready for product validations, testings and sterilization service.
Due to the increased use of heat sensitive, essentially polymer based materials like PE foils
and tubes or PE-coatings, there is a demand for low temperature sterilisation methods.
The sporicidal efficacy of commercial vapour-plasma sterilisers using hydrogen peroxide is mainly due to the chemical effect of the hydrogen peroxide vapour during the diffusion phase, while the plasma phase has a detoxifying nature.
The advantages of this are: low process temperatures (about 45 to 50° C), relatively rapid sterilisation cycle (about two hours), and safe with respect to both the operator and the patient, since there are no toxic residues generated like in the case of EO.

The advantages of this way of sterilisation instead of sterilisation by ionising radiation is mildness to the products and additionally, ionising radiation can induce molecular changes, leading to material property alterations.
Latest material testings show how mild the method of vapour-plasma-sterilisation is for the PVC-bloodlines. Bloodlines those became sterilised a few times under worst-case- conditions were tested, one part at once, the other after artifical aging of three years. The others were tested with regard to biological, toxical and physical changes, but none was found.
The tests achieved very good results, so not the aging, nor the sterilization shows any effect instead of sterility.