Transfection problem - milky media - (Jul/07/2009 )
I am doing Calcium Phosphate transfections in 293T cells and my media turns very milky and cloudy, immediately after mixing all components together. I have been performing DNA transfections successfully for several years and I have never seen this. Although my cells do express GFP they die within 24 hours. I have made new reagents and filtered everything. The crazy thing is... I have also done controls with every component separate and DO NOT see the milky media.
The DNA plasmids are the only thing was not changed, although alone the plasmids do not turn the media milky.
Has anyone seen this before?
I haven't seen it, but it will be a precipitate of some sort, probably a metal ion/protein one.