Classical sterilization techniques using saturated steam under pressure or hot air are the most reliable and should be used whenever possible. Other sterilization methods include filtration, ionizing radiation (gamma and electron-beam radiation), and gas (ethylene oxide, formaldehyde).
When using steam, the substances being sterilized are subjected to steam in autoclave steam heating equipment. The process uses temperatures of up to 115 degrees for an hour. It is the most common method for sterilizing drugs because it can kill the bacterial spores, which are inert bacterial forms.
A medical autoclave is a device that uses steam to sterilize equipment and other objects. This means that all bacteria, viruses, fungi, and spores are inactivated. Because damp heat is used, heat-labile products (such as some plastics) cannot be sterilized this way or they will melt.
Sterilization describes a process that destroys or eliminates all forms of microbial life and is carried out in health-care facilities by physical or chemical methods. Disinfection describes a process that eliminates many or all pathogenic microorganisms, except bacterial spores, on inanimate objects (Tables 1 and 2).
Autoclaves, clean-in-place (CIP) and sterilization-in-place (SIP) systems, dry heat sterilizers and ovens, steam sterilizers, media sterilizers, and UV chambers all work to sterilize equipment and supplies.
Sterilization destroys all microorganisms on the surface of an article or in a fluid to prevent disease transmission associated with the use of that item.
Hydrogen peroxide is a liquid chemical sterilizing agent which is a strong oxidant and can destroy a wide range of microorganisms. It is useful in the sterilization of heat or temperature-sensitive equipment like endoscopes. In medical applications, a higher concentration (35-90%) is used.
Autoclaving kills microbes by hydrolysis and coagulation of cellular proteins, which is efficiently achieved by intense heat in the presence of water. The intense heat comes from the steam. Pressurized steam has a high latent heat; at 100oC it holds 7 times more heat than water at the same temperature.
Boiling is a very simple method of water disinfection. It should be noted that it is designed to kill harmful organisms, and generally does not result in sterile water (free of all microorganisms).
Sterilization of an endoscopeAir should be forced through the internal channels with a syringe to dry them, and the endoscope should be stored in some sterile manner such as covering the endoscope with a sterile wrap or cloth.
Sterilize the medium by autoclaving at 15 lbs or 121°C for 15 minutes. Cool the autoclaved medium to 45°C before adding the filter sterilized heat labile supplements. Dispense the desired amount of medium in sterile culture vessels. Store the prepared medium at 2-8°C away from direct light.
Supplies wrapped in double-thickness muslin comprising four layers, or equivalent, remain sterile for at least 30 days. Any item that has been sterilized should not be used after the expiration date has been exceeded or if the sterilized package is wet, torn, or punctured.
The best method for sterilizing culture tubes is by autoclaving for 30 minutes at 121 °C (15 psi pressure). Media which solidifies on cooling should be poured out while the tubes are hot.
Put a steamer basket and water in the pressure cooking pot. Put your tools into the steamer, close the lid on the pot, and put the pot on a flame to boil. After it comes to a boil, cook at 15 or 20 pounds of pressure for 20 minutes. After sterilizing tools, let them dry.
Temperature. The standard temperature for an autoclave is 121 degrees Celsius. The reason for this is that simply bringing something up to the temperature of boiling water, 100 degrees Celsius (212 degrees Fahrenheit), is not sufficient to sterilize it because bacterial spores can survive this temperature.
Two minutes of microwaving is sufficient for most sterilization. researchers have found that microwaving kitchen sponges and plastic scrubbers — known to be common carriers of the bacteria and viruses that cause food-borne illnesses – sterilizes them rapidly and effectively.
There are multiple ways of having sterilization done, but the two that are used most frequently are tubal ligation for women and vasectomy for men. There are many different ways tubal sterilization can be accomplished. It is extremely effective and in the United States surgical complications are low.
Pasteurization is a process that kills the pathogenic bacteria by heating to a certain temperature for a set period of time. Sterilization kills pathogenic and saprophytic microorganisms, vegetative and spore forms, viruses. Pasteurization only destroys the vegetative forms of the bacteria.
For extra germ removal, sanitize feeding items at least once daily. Sanitizing is particularly important when your baby is younger than 3 months, was born prematurely, or has a weakened immune system.
Sterile mineral oil is indicated for use as a lubricant for surgical instruments. Muri-Lube is not intended for parenteral or oral use.
Generally oil based injections are sterilized by filtration through 0.22 mm membrane filter. For faster filtration, oil is maintained hot to reduce it's viscosity. Also vacuum is applied from other side.
6. All mesophilic nonsporing bacteria are killed on exposure to moist heat at 60˚C for ½ hr, except a few which need a different set of time and temperature of sterilization.
An autoclave is used to sterilize surgical equipment, laboratory instruments, pharmaceutical items, and other materials. It can sterilize solids, liquids, hollows, and instruments of various shapes and sizes.
Chemical indicators should be used in all types of sterilization processes including: steam, hydrogen peroxide, and ethylene oxide.
scientist Antonie van Leeuwenhoek
