I had mammalian cancer cell line cultured and fixed for confocal imaging. While observing I found these particles around cell nuclei stained with dapi. I checked the main culture for bacteria but there was no bacterial contamination. Are these mycoplasma?
Possibly, see Fig 1 of Article The importance of quality control of cultures used in biolog...
A definitive test such as Lonza's MycoAlert kit would give you a yes/no answer (there are others of course). https://bioscience.lonza.com/lonza_bs/TR/en/Cell-analysis/p/000000000000186472/MycoAlert-Mycoplasma-Detection-Kit-%28100-Tests%29
Dear Manita,
It is possible but quite difficult to see mycoplasma with confocal imaging. You can refer to this recent article from the japan CRB Cell Bank to get an idea. Article Discrimination of mycoplasma infection using machine learnin...
This is quite cool (they discriminate contaminated cells with autofluorescence signature) ! The pictures are different from yours. Alternatively you can use our straightforward Mycostrip Kit as in the publication.