Discuss Mechanism of sterilization in detail
Sterilization is the process of destroying all forms of microbial life, including bacteria, viruses, spores, and fungi. There are various methods of sterilization, each with its own mechanism of action. Below are some common methods of sterilization and their mechanisms:
1. Heat sterilization: Heat is the most commonly used method of sterilization. There are two main heat sterilization methods: moist heat (autoclaving) and dry heat. Autoclaving involves exposing the material to high pressure steam at 121°C for a specific amount of time. The high temperature and pressure denature proteins and disrupt cell membranes, ultimately killing the microorganisms. Dry heat sterilization involves heating the material to high temperatures ranging from 160 to 170°C for several hours. Dry heat causes oxidation and coagulation of proteins, leading to the destruction of microorganisms.
2. Chemical sterilization: Chemical sterilization involves using disinfectants or sterilizing agents to kill microorganisms. Chemical agents like ethylene oxide, formaldehyde, and hydrogen peroxide are commonly used for sterilization. These agents work by disrupting the structure of proteins, nucleic acids, and cell walls of microorganisms, ultimately leading to their death.
3. Radiation sterilization: Radiation sterilization uses ionizing radiation, such as gamma rays, electron beams, or X-rays, to kill microorganisms. Ionizing radiation disrupts the DNA and RNA of microorganisms, preventing them from replicating and causing their death. Radiation sterilization is commonly used for sterilizing medical devices, pharmaceuticals, and food products.
4. Filtration sterilization: Filtration sterilization involves passing the material through a filter with small pores that can trap microorganisms. The pore size of the filter determines the efficiency of sterilization. Filtration sterilization is commonly used for sterilizing liquids, such as vaccines, antibiotics, and biological samples.
5. Plasma sterilization: Plasma sterilization involves exposing the material to low-temperature plasma, which is a mixture of ionized gases. Plasma sterilization works by generating reactive oxygen and nitrogen species that can damage the cell membranes, proteins, and nucleic acids of microorganisms, leading to their death.
Overall, sterilization methods work by disrupting the structure and function of microorganisms, ultimately leading to their death and ensuring the sterility of the material. It is essential to select the appropriate sterilization method based on the type of material to be sterilized and the desired level of sterility.