High Yield Synthesis and Application of Magnetite Nanoparticles (Fe₃O₄)

• Main Authors: Charles Wroblewski, Tunde Volford, Blake Martos, Jurek Samoluk, Perry Martos
• Format: Article
• Language: English
• Published: MDPI AG 2020-05-01
• Series: Magnetochemistry
• Subjects: magnetite nanoparticles; synthesis; repeatable; ammonia headspace; super-paramagnetic; tetracyclines
• Online Access: https://www.mdpi.com/2312-7481/6/2/22

Magnetite nanoparticles (Fe₃O₄), average particle size of 12.9 nm, were synthesized de novo from ferrous and ferric iron salt solutions (total iron salt concentration of 3.8 mM) using steady-state headspace NH_3(g), 3.3% <i>v</i>/<i>v</i>, at room temperature and pressure, without mechanical agitation, resulting in >99.9% yield. Nanoparticles size distributions were based on enumeration of TEM images and chemical compositions analyzed by: XRD, EDXRF, and FT-IR; super-paramagnetic properties were analyzed by magnetization saturation (74 emu/g). Studies included varying headspace [NH_3(g)] (1.6, 3.3, 8.4% <i>v</i>/<i>v</i>), and total iron concentrations (1.0 mM, 3.8 mM, 10.0 mM, and >>10 mM). An application of the unmodified synthesized magnetite nanoparticles included analyses of tetracycline’s (50, 100, 200, 300, and 400 ppb) in aqueous, which was compared to the same tetracycline concentrations prepared in aqueous synthesis suspension with >97% extraction, analyzed with LC-MS/MS.