Gamma radiation sterilization can be defined as the controlled exposure of a product to ionizing radiation. A specified dose of radiation, of which will reduce the bioburden to the desired level without damages, is delivered to the product. The ionizing energy produced by the gamma rays penetrates deeply, making it a good fit for products with various densities and packaging types, such as prefilled syringes.

In selecting a resin for particular medical devices, one must consider the effects of the sterilization method on the physical and optical properties. Gamma sterilization causes color shift in most materials, including polycarbonate, ABS, acrylic, and copolyesters that are used in injection molded devices. Understanding the intensity of the color shift caused by gamma sterilization will help you determine which plastic is right for your application.

Various resins have been tested to ascertain their response to gamma sterilization and the results show that Eastman™ resins exhibit very good resistance to gamma sterilization when compared to competitive materials.