Capture and release of genomic DNA by PEI modified Fe3O4/Au nanoparticles

Polyethylenimine (PEI) modified Fe3O4/Au nanoparticles were synthesized in aqueous solution and characterized by photo correlation spectroscopy (PCS) and vibrating sample magnetometer (VSM). The so-obtained Fe3O4/Au-PEI nanoparticles were capable of efficient electrostatic capture of DNA. The maximum amount of genomic DNA captured on 1.0 mg Fe3O4/Au-PEI nanoparticles was 90 μg. The DNA release behavior was studied and the DNA recovery from Fe3O4/Au-PEI nanoparticles approached 100% under optimal conditions. DNA extraction from mammalian cells using Fe3O4/Au-PEI nanoparticles was successfully performed. Up to approximately 43.1 μg of high-purity (OD260/OD280 ratio = 1.81) genomic DNA was extracted from 10 mg of liver tissue. The results indicated that the prepared Fe3O4/Au-PEI nanoparticles could be successfully used for DNA capture and release.