Transfection efficiency vs. amount of plasmid DNA - (May/07/2009 )

Hello,

I'm interested in the general effect of different amounts of plasmid DNA on transfection efficiency, especially for calcium phosphate transfection methods. I'd like to know if there is an optimal amount of DNA, or if it is rather like the more dna the better. Does the curve converge somewhere or is it quadratic etc... We are trying to establish an assay where the importance is on a robust signal rather than on a maximum height signal. I'm a bioinformatician who is supposed to analyse the data. I know that there are other factors as well, but I'm not too deep into this. Basically I'd like to know what we should expect if we do the same experiment but use more dna for the transfection.

Thanks a lot!
Burkster

For most cell lines, the more DNA that is used for transfection, the more "toxic" it is to the cells. That is, for most cell lines anyway, you can expect that you will get increasing cell death with increasing amounts of DNA used for the transfection, usually regardless of the transfection method.

Anywhere from 2 to 8 ug of good quality DNA (OD260/OD280 >/= 1.8) should give good transfection efficiency with minimal cell death. As increasing amounts of DNA are used for the transfection, the transfection efficiency will generally decrease. So, you will often see an increasing transfection efficiency followed by a decreasing transfection efficiency as the amount of DNA used for transfection increases along the X axis.

burkster on May 7 2009, 04:15 AM said: