Protocol Online logo
Top : Forum Archives: : Cell Biology

precipitate formation - transfection with calcium phosphate precipitaion (Nov/27/2006 )

I'm trying transfection my cells with calcium phosphate precipitation method and preparing all solutions by myself. I tested precipitate formation to see cloudyness following a protocal titled calcium phosphate precipitation for MDCK cells, which i got it from internet. I couldn't obviously see cloudyness. Actually i don't know how precipitation could be. Anyone who has experience about this, please give me some informations.


When I do calcium phosphate (on 293T cells), the precipitate is visible as tiny dots that are to be found between the cells and on them. if you gently tapp your cells under the microscope, you will see they move a bit. When adding the CaCl2 to your DNA, you will notice this is more viscuous than the rest and also when you add your DNA/Calcium mixture to your HBS you will see it "fall into it", hard to describe, but it could be that they call this the "cloudiness", but after some seconds, this disappears as it dissolves further into the HBS.

Severall colleagues of mine actually thought the precipitats between the cells to be bacteria and without asking for a second opinion added bleach to the cells to make sure those bacteria wouldn't spread :-) (even when media color didn't change at all...).


Thanks a lot vairus. i think i saw that calcium solution fell into HSB in an early moment afterward it disappeared and became a clear solution. I hope it's right. I'm going to do transfection soon.