A simplified, fast, and effective production method has been developed for the synthesis of manganese ferrite (MnFe₂O₄) magnetic nanoparticles (MNPs). In addition to the wide applicability of MnFe₂O₄ MNPs, this work also reports their application in DNA isolation for the first time. An ultrasonic-cavitation-assisted combustion method was applied in the synthesis of MnFe₂O₄ MNPs at different furnace temperatures (573 K, 623 K, 673 K, and 773 K) to optimize the particles’ properties. It was shown that MnFe₂O₄ nanoparticles synthesized at 573 K consist of a spinel phase only with adequate size and zeta potential distributions and superparamagnetic properties. It was also demonstrated that superparamagnetic manganese ferrite nanoparticles bind DNA in buffer with a high NaCl concentration (2.5 M), and the DNA desorbs from the MNPs by decreasing the NaCl concentration of the elution buffer. This resulted in a DNA yield comparable to that of commercial DNA extraction products. Both the DNA concentration measurements and electrophoresis confirmed that a high amount of isolated bacterial plasmid DNA (pDNA) with adequate purity can be extracted with MnFe₂O₄ (573 K) nanoparticles by applying the DNA extraction method proposed in this article.

For pathogens identification, the PCR test is a widely used method, which requires the isolation of nucleic acids from different samples. This extraction can be based on the principle of magnetic separation. In our work, amine-functionalized magnesium ferrite nanoparticles were synthesized for this application by the coprecipitation of ethanolamine in ethylene glycol from Mg(II) and Fe(II) precursors. The conventional synthesis method involves a reaction time of 12 h (MgFe₂O₄-H&R MNP); however, in our modified method, the reaction time could be significantly reduced to only 4 min by microwave-assisted synthesis (MgFe₂O₄-MW MNP). A comparison was made between the amine-functionalized MgFe₂O₄ samples prepared by two methods in terms of the DNA-binding capacity. The experimental results showed that the two types of amine-functionalized magnesium ferrite magnetic nanoparticles (MNPs) were equally effective in terms of their DNA extraction yield. Moreover, by using a few minutes-long microwave synthesis, we obtained the same quality magnesium ferrite particles as those made through the long and energy-intensive 12-h production method. This advancement has the potential to improve and expedite pathogen identification processes, helping to better prevent the spread of epidemics.

• pDNA and gDNA can be extracted from bacterial cells using magnetic nanoparticles. • A cost-effective DNA isolation method was developed with MNPs. • High quality and quantity DNA isolation with magnetic nanoparticles. • Comparison of traditional, MNP-based and column-based DNA isolation.