I have recently performed serial dilution of several different cell lines in 96-well plates to isolate single clones. After several weeks of growth, I started to notice bacterial contamination in one well, then a few more wells, of different plates, plated on different days. I'm trying to figure out how individual wells could have become contaminated after plating (I assume it was after because nothing showed up for weeks). More of the contaminated wells seemed to be on or near the perimeter of the plates. Is it possible for a contaminant to spread using the moisture which often forms inside the plate lid as a conduit?
The cells are growing in penn/strep as well as two selection antibiotics.
Edited by Artemis2007, 06 May 2015 - 11:45 AM.