Study On The Dose Setting Methods Of Medical Devices And On The Application Of Radiation Sterilization

Objectives On the basis of practical application combined with the current domestic study, to provide evidences for the selection of appropriate dose setting method. At the same time, through systemic study on 3M Steri-Drape, to show the potential influence of radiation on polymer material.Methods The 148 samples collected were from 52 manufacturers all over our country. After bioburden estimate, the dose setting was performed with ISO11137 method 1, along with other two method (1g method and VDmax(-1) method. Andthe application of radiation on 3M Steri-Drape was given from the angles of package, physical and chemical properties and biocompatibility under the dose setting with ISO11137 method 1.Results The bioburden on product ranges from 7.17 to 1.98 105cfu/unit. Different dose setting methods: in ISO11137 method 1, the verification dose is from 3.1 to 8.7KGy(SAL=10-2), and the responding sterilization dose is from 17.2 to 33.7KGy(SAL=10-6); in 1g method, the sterilization dose is from 11.67 to 19.21 KGy(SAL=10-6) ; to the products with bioburden less than 1000cfu/unit, the verification dose of VDmax(-1) ranges from 6.9 to 9.1 KGy(SAL=10-1), and the rational verification dose is from 10.4 to 13.7 KGy. On the same level of bioburden, the sterilization dose from ISO11137method 1 is more than that from 1g method. They both less than VDmax (-1).Test of dose verification: ISO11137 method 1 occur a verification failure.Before and after irridation, the package, physical and chemical properties of products and biocompatibility of 3M Steri-Drape were not affected significantly. And the clinical application is safe. Conclusions 1) The effect of bioburden remove are related with both the ability of remove technique and the property of product.2) The VDmax(-1) method is perfect for product with less contamination, ISO11137method 1 is perfect for product produced regularly. The dose safty of Ig method which used widely in china is suspicious.Moreover, combined with domestic study, a more safe and less dose could be fulfilled.3) The reasonable dose setting could less or avoid the adverse affection from Y -ray on product.