Development of methods for fabricating nanoparticles composed of magnetite, gold, and silica toward diagnostic imaging

Nontoxic nanoparticle contrast agents with multiple imaging functions are required for medical diagnostic imaging, and coating the less toxic materials meets this requirement. This work proposes a method fabricating magnetite, gold (Au), silica nanoparticles toward imaging. The proposed involved four steps: synthesis of magnetite (Fe3O4) nanoparticles, Au formation composite Fe3O4 (Fe3O4/Au), Fe3O4/Au nanoparticles. 6.3 ± 1.2 nm-sized was performed via salt-based reaction in an aqueous solution containing FeCl3, FeCl2, citric acid, HCl, NaOH. 2.2 0.4 reduction HAuCl4 tetrakis (hydroxymethyl) phosphonium chloride, sol–gel ethanol poly-diallyldimetheylammonium tetraethylorthosilicate, NaOH, water under sonication. Fe3O4/Au/SiO2 were degraded fetal bovine serum/phosphate-buffered saline solution, PEGylated (Fe3O4/Au/SiO2–PEG) adsorbed protein after PEGylation, Fe3O4/Au/SiO2–PEG had magnetic property X-ray ability, revealing that expected to function as safe excretable agent MRI X-ray.