SterilizationSterilization

Definition

sterilization (or sterilisation) is a term referring to any process that eliminates (removes) or kills (deactivates) all forms of life and other biological agents

ApplicationsMedicine and surgery:-

surgical instruments medications that enter an already aseptic part of the body (such as the bloodstream, or penetrating the skin) must be sterile. scalpels, hypodermic needles  artificial pacemakers. This is also essential in the manufacture of parenteral pharmaceuticals

Sterilization Methods

Physical method Chemical method

radiation, heat and filtration

liquid and gas disinfectant

1-Heat•Dry Heat

red heat

hot air oven

microwave

Moist heat

Pasteurization

Simply Boiling or steam heat

Autoclave

2-Radiation

electron beams,  X-rays,  gamma rays, or irradiation bysubatomic particles. Non-ionizing radiation sterilization Ultraviolet light irradiation (UV, from a germicidal lamp) is

useful for sterilization of surfaces and some transparent objects. Many objects that are transparent to visible light absorb UV

Ionizing radiation sterilization Gamma radiation is very penetrating, and is commonly used

for sterilization of disposable medical equipment, such as syringes, needles, cannulas 

3-FiltrationThis method is commonly used for heat labile pharmaceuticals and protein solutions in medicinal drug processing. It can be sterilized by microfiltration using membrane filters

Chemical sterilization Gas: Ethylene oxide (EO or EtO) gas Liquid: Alcohol 70% Ethyl alcohol used as skin antiseptic Phenol as 5% used as disinfectant Aldehydes as 2% formaldehyde used as sterilizant Surface active agents as anionic surfactant as soap and cationic

surfactant as quaternary ammonium compounds