What is the situation of culture dish contamination? What are the countermeasures for each of them?
Petri dishes are commonly used instrument consumables in the laboratory and medical field, and they are required to be sterile. It is used to culture other bacteria and microorganisms, and if it carries bacteria itself, it will cause culture failure or incorrect culture.
Incubation of substances in Petri dishes
But there are always exceptions to everything, if the petri dish is accidentally contaminated with bacteria, we must first find out the cause of the contamination, and then take further measures. About the petri dish contamination, generally divided into two situations, namely, their own contamination and unpacking operation improper contamination.
The special case of self-staining bacteria, specifically can also be divided into three situations.
1, the manufacturer production control is not strict, the microbial load before sterilization is too large. That is to say, from the root is not completely sterilized, the reproduction rate of bacteria and good, in a relatively more closed environment a large number of breeding is not uncommon.
2, gamma sterilization dose is low (mold tolerance is strong).
3, packaging breakage appeared in the secondary contamination. This although it seems like the second case we mentioned above, but in fact, also culture dishes in the formal unpacking occurred before, so also belongs to its own contamination category.
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The second case is the use of improper occurrence of bacterial contamination problems (equal chance of bacteria mold, mostly on the surface of the medium or agar and the edge of the flat dish)
1, small package use of the remaining temporary storage (refrigerator or A-class area)
2, unpacking in the general area transfer window to remove three layers of packaging in a single special case.
3.The movement amplitude is too large when unpacking, and the flat dish is scattered.
4, the above two will appear in the special contamination phenomenon, the bacteria in the edge of the flat dish growth, or extended flat dish and medium gap growth of special cases. (This is usually related to the packaging vacuum, airflow backward suction).
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Therefore, we found that we can't stop the situation of those self-staining bacteria in time, but we can find it in time. For the bacteria caused by improper operation, it is necessary to strengthen the aseptic awareness of operators and regulate the whole operation process.
Petri dishes are a very special class of instrument consumables, which are related to the life and health of many people, so it is necessary to establish the right attitude and treat petri dishes seriously.
