Are pDNA that are cloned with the genes of interest less efficient? are there any drawbacks? Any drawbacks in relation with lipofectamine or using them with HeLa or HEK 293?
Proteins present in serum such as FBS and FCS can inhibit various transfection reagents, and thus significantly reduce the transfection efficiency. We usually use Opti-MEM from Life technologies which is a serum-free medium for transfection. This works well with HEK293, HEK293T, Hela cells using Lipofectamine.
Usually not. Lipofectamine and other related transfection compounds can be used to to transfect very large DNA molecules, so, even if your gene of interest was very long, it is not expected any kind of problem.
Proteins present in serum such as FBS and FCS can inhibit various transfection reagents, and thus significantly reduce the transfection efficiency. We usually use Opti-MEM from Life technologies which is a serum-free medium for transfection. This works well with HEK293, HEK293T, Hela cells using Lipofectamine.
We use regular DMEM with Lipofectamine for HEK, He La and usual endothelial lines. There is absolutely no issue, but yes you should standardize your DNA: Lipo ratio to avoid unnecessary cell death or toxicity. This is very specific to how your protein when overexpressed may cause cell death as well. Opti-mem is good and reagents from Mirus are also good in transfection efficiency.