Fundamentals of Microbiology

2.2.7 Chemical sterilization

Ethylene oxide (EtO) - It is effective microbicidal and sporicidal agent. It combines with cell protein and causes denaturation. It is capable of penetrating packaging materials and used for sterilization of plasticwares, tubings, etc. The materials to be treated are exposed to EtO at the concentration of 700 mg / lit for 5 to 8 hours at 38^oC or 3 to 4 hours at 54^oC. Excessive aeration is required after the treatment to remove the EtO residue in treated materials.

Other chemical sterilizing agents are Betapropiolactone (BPL) - sterilizing gas and vapour phase of H₂O₂.