Fungal Contamination? - Suspension culture (Dec/20/2010 )

I am using a culture model for suspension cells (neurospheres) which contains pen/strep in the media and have had no issues with it for the last weeks, but came in this morning and there were a few (maybe 6) fuzzy flower looking things (look like a gray water lily) growing on the surface of the media. I'm suspecting a fungal contamination at this point. Media looks clear under 60X microscope--the stuff is only growing on the surface. Only showed up in 2 of the 30 flasks. Checked cells 24 hours before and didn't notice anything, so these must be pretty fast growing. Incubator was cleaned the week before. It is a low 02 incubator as well. I have put out media in dishes to see if I can figure out what it is coming from.

Any ideas?

Thanks!

-bk9-

I'm agree with you, it has to be fungal contamination, throw away the contaminated flasks and pray for the others stay clear. Spores are everywhere and are very difficult to remove.
Good luck

-Irene G-

bk9 on Mon Dec 20 19:41:05 2010 said:

Dear bk9,

99% of the time fungal contamination will be coming from the CO2 Incubator. Flasks and dishes need to be wiped with 70% IMS before being put back in the incubator. Direct heat incubators have no fan units and are easier to clean and maintain. Regular water changing i.e. every week will also reduce the chance of fungal contamination.

Try and grow all cells in flasks with a filtered top (0.22uM) which will act as a barrier for all forms of contamination.

Hope this is useful.

Kindest regards.

Uncle Rhombus.

-rhombus-