Sterilization and Disinfection Practical I

Disinfection and Sterilization Overview

• Disinfection: Procedure aimed at reducing microorganisms significantly but does not eliminate bacterial spores; employs physical and chemical methods.
• Sterilization: Complete removal or destruction of all forms of microbial life, including bacterial spores, with no absolute guarantee of zero microorganisms remaining.

Methods of Sterilization

• Physical Methods:

  • Heat: Effective in killing microorganisms; includes dry heat and moist heat.
  • Radiation: Uses ionized and non-ionized radiation to achieve sterilization.

• Chemical Methods: Involves the use of various chemical agents to destroy microorganisms.

Physical Methods of Sterilization

• Heat Sterilization:
  • Dry Heat: Utilizes high temperatures to kill microorganisms.
    • Direct Flaming: Involves holding metal instruments (loops, wires, glass slides) in a Bunsen flame until red-hot; can be pre-treated with disinfectants.
    • Alcoholic Flaming: Sterilizes metal tools (forceps, scissors, scalpels) effectively using flames from alcohol-soaked materials.
  • Moist Heat: Involves steam under pressure (e.g., autoclaving) to achieve higher efficiency in killing microorganisms.

Importance of Understanding Resistance

• Different microorganisms exhibit varying levels of resistance to sterilization methods, making it crucial to select appropriate techniques for effective sterilization.

Test your knowledge of the principles and procedures of sterilization and disinfection. Learn about the methods used to reduce microorganisms and completely eliminate all forms of microbial life.