Cobalt–zinc ferrite and magnetite SiO2 nanocomposite powder for magnetic extraction of DNA

• DOI: 10.1007/s10971-019-05017-z
• Publication Date: 2019-05-11T14:58:10Z
• Authors: Jorge Torres-Rodr...; Gerardo Soto; Javier López Medina; Amelia Portillo-L...; Edna Lorena Herná...; Eunice Vargas Viv...; José Trinidad Eli...; Hugo Tiznado; Dora-Luz Flores; Franklin Muñoz-Muñoz
• Keywords: 02 engineering and technology; 0210 nano-technology

Magnetic nanoparticles are currently used as building blocks for the fabrication of various functional systems. In this work, magnetic cobalt–zinc ferrite (Co0.25Zn0.75Fe2O4) and magnetite (Fe3O4) nanoparticles were prepared by the co-precipitation method. After that, the nanoparticles were coated with silica (SiO2) via a modified Stober sol–gel method. The resulting materials are fine powders which were characterized by X-ray diffraction, electronic microscopies, energy-dispersive X-ray spectroscopies, and a vibrating-sample magnetometer. Those techniques showed the formation of nanoparticles embedded in an amorphous matrix of SiO2. The particles measured between 10 and 40 nm exhibited small hysteresis loops, as soft magnets. A protocol for magnetic extraction of deoxyribonucleic acids (DNA) was carried out using these powders. DNA purity was evaluated under UV-VIS spectrophotometry and agarose gel electrophoresis. The composites based on cobalt–zinc ferrite are as good as the magnetite nanoparticles, and we showed that both of them could be used to purify nucleic acids.