I constructed a plasmid, and extracted more than 500ug plasmid. I transfected it with four different reagent treatments, including two kind of nanoparticles ,pei and lipofectamin 3000. as a sample in working with lipofectamin 3000 i transfected 1ug plasmid with 3ul of lipofectamin3000. I didn't get any results and my cells died every time. I have this problem and I don't know how to solve it. can any one please give me an ideas and help me salving this problem.

thanks.