Disinfection & Sterilization Lecture 2

Disinfection is the killing of all microorganisms, including bacterial spores.

Antiseptics are chemicals used to achieve disinfection on surfaces of skin and mucous membranes.

Sterilization is usually carried out by autoclaving at 100ºC under pressure.

Glassware and medium are routinely sterilized by using ethyl oxide gas.

Surgical instruments that can be damaged by moist heat are usually sterilized by autoclaving.

Disinfectants are used to achieve sterilization.

The method of dry heat sterilization involves the use of hot water vapor as a sterilizing agent.

Temperatures between 150 degrees Celsius and 200 degrees Celsius are usually applied for a sustained period in modern dry heat sterilization.

Moist heat sterilization is a technique that uses hot air as a sterilizing agent.

Direct flaming is used for sterilization of metal instruments such as scalpels and scissors.

All dry glassware and metal instruments are usually sterilized by moist heat.

High temperatures are applied to a substance to remove microbial life, including viruses and fungal spores.

Incineration is a method of sterilization that uses steam under pressure.

Boiling is a reliable method for killing spores.

Autoclaves are used for sterilizing materials that cannot withstand high temperatures and pressure.

Filtration is a method of sterilization that uses heat.

Hot Air Oven is used for sterilization at a temperature of 160-180ºС for one hour.

Incineration is a method of moist heat sterilization.

Ultra-violet rays are used for the sterilization of fluids that do not withstand heating.

Mercuric salt is used as a preservation for sera and vaccines.

Isopropylalcohol is used to sterilize the skin before injection or vein puncture, not surgical instruments.

Radiation induces thymine dimmers in DNA, which enhances the replication of microorganisms.

Phenols are used to sterilize thermometers.

Silver salt is used to prevent infections by Neisseria gonorrhea in newborn infants.