Magnetic extraction and purification of DNA from whole human blood using a γ-Fe 2 O 3 @Chitosan@Polyaniline hybrid nanocomposite.

We examined the properties of the nanocomposite γ-Fe2 O3 @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 (qe ) of the nanocomposite as 49.5 mg/g. We also observed that the kinetic model of the DNA capture presents a mixed character, with both chemical mechanisms and intraparticle diffusion processes involved. When the MNC was used to extract the DNA from complex samples (human blood), a capture rate of 80 ng/μL was achieved, with the collected fraction exhibiting good quality, as evaluated by PCR analysis and electrophoresis assays. These results suggest that the γ-Fe2 O3 @Chi@Pani nanocomposite is a promising adsorbent for use in protocols for purification of DNA from complex samples.