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Sterilization techniques - Coggle Diagram
Sterilization techniques
Autoclave
Heat (121 Deg C) and steam under pressure
Coagulate and denature proteins
Cells die at lower temperature when hydrated
Will cause polymers to warp if higher than Tg
Radiation
Creates free radicals in water that diffuse into microorganisms and damages DNA
Break down polymer chain weakening mechanical properties
Can cause discloration
Gamma Rays
Higher penetration
Isotope needs replacing
Electron beam sterilization
Faster than gamma ray
EtO sterilization
Usage of EtO gas
Can be used on polymers as has no effect
Fully packaged materials that have thin films can be sterilized
Is toxic and carcinogenic
Poses threat to envrioment
Gas causes alkylation of amine groups on nuclei acid
Has to be preconditioned for 24 hours with humidity as dry organisms more reistant
Most suitable technique: EtO sterilization
Radical sterilization can weaken mechnical properties by chain scission and turn polymer yellow
Autoclave process will warp polymer
EtO can permeate HDPE packaging and sterilize contents
EtO sterilization won't affect HDPE packing
However must remove residual EtO as toxic