Extraction of plasmid DNA by use of a magnetic maghemite-polyaniline nanocomposite.

We describe the use of a hybrid magnetic nanocomposite (HMNC) for the extraction and purification of plasmid DNA (pDNA) from Escherichia coli aqueous solutions. The HMNC, which was synthesized via emulsion polymerization, was characterized by transmission electron microscopy, scanning electron microscopy, UV-Vis spectroscopy, Fourier transform infrared spectroscopy, dynamic light scattering and magnetic measurements. The results confirmed the incorporation of polyaniline (Pani) in its conducting form onto a core formed by the magnetic iron oxide, with the hybrid particles presenting an average size of (95 ± 30) nm and a saturation magnetization of 30 emu/g.

Magnetic extraction and purification of DNA from whole human blood using a γ-FeO@Chitosan@Polyaniline hybrid nanocomposite.

We examined the properties of the nanocomposite γ-FeO@Chi@Pani as an adsorbent of deoxyribonucleic acid (DNA). As a model system, we used an aqueous solution of salmon sperm DNA, whose decreasing concentration was followed by monitoring the 260 nm UV-vis absorption. After adjusting the data collected to a Langmuir isotherm curve, we estimated the adsorption capacity (q) of the nanocomposite as 49.

Use of magnetic polyaniline/maghemite nanocomposite for DNA retrieval from aqueous solutions.

We demonstrated that the magnetic polyaniline/maghemite nanocomposite (Pani/γ-Fe2O3 MNC) is an efficient agent for retrieval of pure double stranded deoxyribonucleic acid (dsDNA) chains from aqueous solutions. The dsDNA chains used in the retrieval experiments were of sodium salt of Salmon Sperm DNA. Based on λ=260 nm absorption measurements, we have employed UV-Vis spectroscopy to estimate the concentration of DNA present in solutions, before and after the interaction with the MNC.