Due to the higher dose rate, less exposure time is needed and thereby any potential degradation to polymers is reduced. Sterilization is used for food, medicine and surgical instruments. Useful for materials which can not withstand high temp. The metallic end of the loop is heated to red hot on the flame. The water in the autoclave boils when its vapor pressure equals that of surrounding atmosphere. Incineration is done especially for inoculating loops used in microbe cultures.
Sterilization can be done by three methods: physical, chemical and physiochemical. Several hours are needed for exposure and flushing out the gas, which can be toxic to humans. They have low absorbing property and are available in different pore sizes. The Germicidal Action of Freezing Temperatures upon Bacteria. May swell rubber or harden plastics.
If the water is boiled for about 20-30 minutes then it destroy all type of and. Moist heat kills microorganisms by denaturation and coagula-tion of proteins. Another problem is that gas flames may leave carbon or other residues on the object if the object is not heated enough. Hence, it is not recommended for sterilizing instruments used for surgical procedure. This method is fast and effective for most hospital wastes, but not for metals and heat-resistant glass materials.
When using any type of gas sterilizer, prudent work practices should include good ventilation, a continuous gas monitor for hydrogen peroxide and good work practices and training. Disinfection may not necessarily eliminate spores or all of the microorganisms from an object or environment. Ultrasonic devices are used in dental and some medical offices to clear debris and saliva from instruments before sterilization and to clean dental restorations. Chemical Methods of Control Chemical agents are generally not intended to achieve sterilization. Different methods Disinfection The different methods include physical or chemical methods. Gasses used for sterilization are very poisonous.
Using Steam : Here the substances are subjected to sterilization in an autoclave a equipment. Antibiotics are also completely ineffective against viruses, such as Norwalk virus and influenza. It is widely employed for embalming purposes. Carbon dioxide is added to minimize the chances of an explosion. The third day re-ensures killing of all the spores by their germination to vegetative forms.
Nonionizing radiations: Nonionizing radiations includeinfrared and ultraviolet radiations. This group includes ozone, hydrogen peroxide, potassiumperman- ganate, and peracetic acid. Irradiation is used by the to sterilize mail in the area. Physiochemical is a combination of physical and chemical method. Used to reduce microbes responsible for spoilage of beer, milk, wine, juices, etc. Require 2 hours at 170oC for sterilization.
But one needs to maintain minimum sterilization time or minimum contact time for the heat to be in touch with microbes or and thereby kill them. This substance is used to disinfect surfaces and objects in 0. One variant keeps the radioisotope under water at all times and lowers the product to be irradiated in the water in hermetically-sealed bells; no further shielding is required for such designs. Status of cleanliness Disinfection Adequate cleanliness Sterilization Absolute or extreme cleanliness 4. It is chemically unstable which can convert into sodium chlorate. Material to be sterilized should be perfectly dry. They have high adsorbing capacity and tend to alkalinize the filtered fluid.
Some of the chemical sterilization methods are described here:- Ozone sterilization of water Ozone is a highly effective sterilization chemical for water. It has the benefit of being able to most organic matter. The sterilant gas manufacturers include many safety features in their products but prudent practice is to provide continuous monitoring of exposure to ozone, in order to provide a rapid warning in the event of a leak. Asepsis : — Technique by which the occurrence of infection into an uninfected tissue is prevented. An alternative type of filter is sintered glass filters. But the solution might get absorbed by the filter pad itself. The concentration of a chemical agent can determine if it can be used as a disinfectant or an antiseptic.
The Methods of Sterilization include 1. These are disposable and single-use discs available in different grades. This technique is named after Louis Pasteur who devised this method. Mutation of Phytomonas Stewartii by X-Ray Irradiation. Certain other methods of sterilization at below 60°C temperature are: Vaccine bath contaminating bacteria in a vaccine preparation can be inactivated by heating in a water bath at 60°C for one hour , Serum bath the contaminating bacteria in a serum preparation can be inactivated by heating in a water bath at 56°C for one hour and inspissation to disinfect egg and serum containing media by keeping then in the slopes of an inspissator heated at 80-85 °C for 30 minutes on three successive days. For powders and other dry forms, it is hot air oven if thermostable or gaseous methods and radiation.
Sonication also forcefully dislodges foreign matter from objects. These filters are circular porous membranes and are usually 0. Sterilization by boiling is facilitated by addition of 2% sodium bicarbonate to water. These include a thermocouples, b chemical indicators, and c bacteriological spores as mentioned below: a. Materials which are sterilized using this type of radiation do not become radioactive, and irradiation of food does not change its nutritional value. Dry heat is transfers heat less effectively to a cool body, than moist heat.