Notes on Sterilization of Pipette Tips
"Some pipettes can be AUTOCLAVE. If they can be autoclaved, the instructions and the pipette will indicate autoclave. Pay attention. The pipette is less sterilized, unless it is used for some special operations, such as RNA. Extraction, etc. If you are worried about contamination and the pipette cannot be autoclaved, wash the tip of the pipette with 75% ethanol. For RNA extraction, use 75% ethanol without RNase contamination.
1. Why do you need to put newspapers for tip sterilization?
Place in a pipette tip box for moist heat sterilization. 121 degrees, 15-20 points. In order to avoid the problem of water vapor, newspaper can be wrapped around the tip box, or it can be dried in an incubator after sterilization.
2. Why should the tip box be sterilized by wrapping it in newspaper when autoclaving?
The second is to avoid too much water in the newspaper package, it can absorb water, and the most important thing is to prevent re-contamination! However, if it is not packaged, it will not have much impact. After sterilization is completed, if there is a lot of water, it can be stored in the oven for a longer time!
3. Should the entire pipette be sterilized when extracting RNA?
The gun generally does not need to be sterilized! If it is really necessary, put it on the ultra-clean workbench and irradiate it with ultraviolet light for half an hour!
4. Matters needing attention when sterilizing the pipette tip during RNA extraction
Use ordinary EP tubes and pipette tips. Before autoclaving, soak in DEPC water overnight to remove RNase. After removing DEPC the next day, put them in a pipette tip box for moist heat sterilization. 121 degrees, 15-20 points. In order to avoid the problem of water vapor, newspaper can be wrapped around the tip box, or it can be dried in an incubator after sterilization. It is best to sterilize directly before each extraction, and it is best not to use long-standing pipette tips to extract RNA. Domestic tubes should still be sterilized, otherwise it will easily degrade, especially for some cells or tissues with high RNase content.
Finally, I heard that some people did not use DEPC water to treat the pipette tip. The RNA extraction result page is not bad, but this is also uncertain. It is recommended that everyone operate in a down-to-earth manner to avoid the experiment and do not know where to find the cause except for the problem.