Synthesis of iron oxide nanoparticles for DNA purification

Sonochemistry in combination with a combustion procedure was used to prepare superparamagnetic iron oxide nanoparticles. Two different iron precursors, ferrocene and iron(II)-acetate were dispersed in polyethylene-glycol (PEG) with different molecular weight (200–1000) by using a high efficiency ultrasonic technique. The sonochemical treatment initiated the precipitation of iron-hydroxide particles, then the PEG based colloids were burnt to create the iron oxide nanoparticles. Three phases were observed in the samples, magnetite (Fe3O4), hematite (α-Fe2O3), and maghemite (γ-Fe2O3) and their ratio can be modified by changing the iron precursor and the type of PEG. Elektrokinetic (Zeta) potential and the particle size of the synthesized iron oxide nanoparticle samples were measured and the one (A1) based on iron(II)-acetate and PEG200 have been selected to test in DNA purification, because it has negative and small size distribution. The synthesized superparamagnetic nanoparticles have been used successfully in biological isolation (DNA, deoxyribonucleic acid purification), and thus, the developed synthetic procedure is more than suitable for such applications. HighlightsSonochemical-combustion method was used to synthesize superparamagnetic nanoparticles.Magnetite, hematite and maghemite nanoparticles were synthesized.The ratio of the iron oxide phases can be tuned by changing the precursors.High molecular weight PEG promote the formation of maghemite and hematite.High molecular weight PEG inhibits the formation of magnetite.The prepared nanoparticles are applicable for DNA purification.