Introduction

The recent and very fast increase in the use of single-use solutions for bioprocessing has impacted the entire supply including the final sterilization step. Sartorius Stedim Biotech is willing to anticipate potential supply risks in the future and is looking to enlarge the capacities and flexibility of single-use products sterilization process, currently performed via Gamma irradiation. For this reason, other irradiation technologies can be envisaged such as e-beam or X-ray. The impact of X-ray sterilization in comparison with the gamma impacts taken as reference on materials and products has been evaluated with a specific risk analysis. The objective is to provide scientific evidence that the performances, specifications & properties are equivalent whether the final single-use product is gamma or X-ray sterilized.

Approach

An approach has been built to understand the effects of X-ray on several levels: raw materials, components, sub-assemblies, and final single-use product levels. Different properties have been evaluated such as thermal properties, chemical properties, or mechanical properties. These material properties were studied up to the end of the shelf life for both irradiation modalities (X-ray and Gamma). To compare the results obtained, a statistical approach is applied based on equivalence criteria. Multivariate analysis is used to differentiate the effects of Gamma and X-ray irradiation on the chemical fingerprint of the material (Figure 1–Example on EVA multilayer film). Equivalence test and polymer science knowledge are other ways to prove the equivalency between Gamma and X-ray irradiation.

Conclusion

The current results obtained to compare Gamma and X-ray irradiation impact on EVA multilayer film show equivalent properties.