High Pressure Steam Sterilization Experiment
High Pressure Steam Sterilization Experiment
The autoclave experiment is applied to: sterilization. High-pressure steam sterilization is the items to be sterilized in a closed pressurized sterilizer pot, through the heating, so that the water between the sterilizer compartment set of boiling and produce steam. To be water vapor dramatically drive the cold air in the pot from the exhaust valve, and then close the exhaust valve, continue to heat, at this time, because the steam can not overflow, and increase the pressure in the sterilizer, thus increasing the boiling point, get higher than 100 ℃ temperature. Resulting in bacterial protein coagulation and denaturation to achieve the purpose of sterilization.
Operation method
High Pressure Steam Sterilization Experiment
Principle
High-pressure steam sterilization is to be sterilized items placed in a closed pressurized sterilizer pot, through heating, so that the water between the sterilizer compartment set of boiling and produce steam. To be water vapor dramatically drive the cold air in the pot from the exhaust valve, and then close the exhaust valve, continue to heat, at this time because the steam can not be overflowed, and increase the pressure in the sterilizer, thus increasing the boiling point, get higher than 100 ℃ temperature. Resulting in bacterial protein coagulation and denaturation to achieve the purpose of sterilization.
Materials and Instruments
Items to be sterilized Move 1. First, remove the inner sterilizing drum, then add an appropriate amount of water to the outer pot so that the water surface is level with the triangular shelf. Caveat 1. The sterilization package should not be too large and too tight (volume should not be greater than 30cm x 30cm x 30cm), the total amount of items placed in the sterilizer should not exceed 85% of the volume of the sterilizer cabinet. Between the packages to leave a gap, so as to facilitate the circulation of steam, penetrate the center of the package, exhaust steam quickly discharged to keep the items dry. 2. Containers should have holes to hold items, if there is no hole, the container lid should be opened. 3. Cloth items are put on top of metal and enamel items. 4. In the use of autoclave sterilizer sterilization, sterilizer cold air exclusion is extremely important, because the expansion pressure of the air is greater than the expansion pressure of the water vapor, so when the water vapor contains air, at the same pressure, the temperature of the air-containing steam is lower than the temperature of the saturated steam. Common Problems In the use of high-pressure steam sterilizer sterilization, sterilizer cold air exclusion is extremely important, because the expansion pressure of air is greater than the expansion pressure of water vapor, so when the water vapor contains air, at the same pressure, the temperature of the air-containing steam is lower than the temperature of saturated steam. For more product details, please visit Aladdin Scientific website.
Beef Peptone Medium
Petri dishes Portable autoclave
2. Put back the sterilizing bucket, and load the items to be sterilized. Be careful not to load too crowded, so as not to prevent the steam flow and affect the sterilization effect. Do not contact the mouth end of the triangular flask and test tube with the barrel wall, so as to prevent condensation from wetting the paper of the package mouth and penetrating into the cotton plug.
3. Cover the lid and insert the exhaust hose on the lid into the exhaust slot of the inner sterilization drum. Then tighten the two opposite bolts in a two-by-two symmetrical manner at the same time so that the bolts are loosened and tightened in the same way and do not allow air leakage.
4. Use electric stove or gas heating, and at the same time open the exhaust valve, so that the water boiling to remove the cold air inside the pot. When the cold air is completely exhausted, close the exhaust valve, so that the temperature inside the pot with the increase in steam pressure and gradually rise. When the pressure in the pot rises to the desired pressure, the heat source is controlled and the pressure is maintained for the desired time. For this experiment, 1.05 kg/cm2, 121.3°C and 20 minutes were used for sterilization.
5. After the required time for sterilization, cut off the power supply or turn off the gas and let the temperature inside the sterilizer drop naturally. When the pressure in the pressure gauge drops to 0, open the exhaust valve, loosen the bolts, open the lid, and take out the sterilized items. If the pressure is not reduced to 0, open the exhaust valve, it will be due to a sudden drop in pressure in the pot, so that the medium in the container due to the internal and external pressure imbalance and rushed out of the mouth of the flask or test tube, resulting in cotton plugs contaminated with the medium and contamination occurs.
6. will be taken out of the sterilized medium into the 37 ℃ incubator culture 24 hours, after checking if there is no growth of stray bacteria, can be used.