Common sterilization methods for medical-grade plastics include ethylene oxide gas, radiation (gamma and electron beam), and low-temperature hydrogen peroxide processes, selected based on material compatibility and device requirements.
Ethylene Oxide (EtO)
EtO gas penetrates packaging and complex shapes at low temperatures (around 30-60°C), making it ideal for heat-sensitive plastics like polyethylene, polypropylene, and PVC. It requires aeration to remove residuals but achieves high sterility assurance levels (SAL 10^-6).
Radiation Methods:
Gamma irradiation from cobalt-60 offers deep penetration for bulk, pre-packaged items like syringes and catheters, though it may cause polymer chain scission or discoloration in some materials. Electron beam (E-beam) is faster with less penetration, suiting thinner plastics without significant property changes.
Hydrogen Peroxide Processes:
Vaporized hydrogen peroxide (VHP) and hydrogen peroxide gas plasma suit temperature-sensitive devices, leaving no toxic residues and working quickly in vacuum chambers. These avoid heat damage to plastics like polycarbonate.
Description provided by indian stalwart global sourcing company.