Stable aqueous dispersions of bare and double layer functionalized superparamagnetic iron oxide nanoparticles for biomedical applications

Abstract

Superparamagnetic iron oxide nanoparticles (SPIONs) have attracted the particular interest of scientists from various disciplines since their obtaining to the present day. The physicochemical and pharmacokinetic properties of SPIONs-containing magnetic nanofluids, and their applicability in biomedicine, largely depend on the stability of the colloidal system, particle size, size distribution, net magnetic moment, phase composition, and type and properties of stabilizers. Also, in some cases, when using magnetic nanoparticles for biomedical purposes, it is necessary that the stabilizing ligands of nanoparticles should not significantly change the magnetic properties. From this point of view, the preparation of stable colloidal systems containing bare iron oxide nanoparticles (BIONs) in water at physiological pH attracts particular attention and becomes increasingly popular in scientific circles. This study is focused on the development of the synthesis of aqueous suspensions of SPIONs stabilized with various organic molecules (oleic acid [OA] and poly(ethylene glycol) monooleate - with molecular weights 460 and 860) using a modified controlled chemical coprecipitation reaction, as well as stable nanofluids containing BIONs in an aqueous medium at neutral pH (near-physiological). The obtained samples were characterized using X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy, small-angle x-ray scattering (SAXS), dynamic light scattering (DLS), electrophoretic light scattering (ELS), and Vibrating Sample Magnetometry.

Synthesis and Characterization of Citric Acid-Modified Iron Oxide Nanoparticles Prepared with Electrohydraulic Discharge Treatment

“…This is also proven by visual observation of the samples after 7 months storage time ( Figure 7 ). According to our previous studies, electrostatic stabilization employing CA coating provides stability for the magnetic fluids in the range of 8–12 month [ 34 ].…”

“…In particular, surface modifications are required to avoid agglomeration, as bare nanoparticles have insufficient long-term stability. They require hydrophilic and biocompatible surface coverage before they may be used in medical applications [ 33 , 34 , 35 ]. Alternative methods for synthesis and stabilization involve more elaborate procedures, such as a novel approach using microfluidics [ 36 , 37 , 38 ].…”

Synthesis, Characterization, and In Vitro Cytotoxicity Evaluation of Doxorubicin-Loaded Magnetite Nanoparticles on Triple-Negative Breast Cancer Cell Lines

“…The zeta potential of the aqueous magnetic nanosuspension containing bare iron oxide nanoparticles is positive [ 46 , 49 ]. This value of the zeta potential ensures the preservation of the colloidal stability of the nanofluid (for certain time) at a pH value close to physiological.…”

“…It should be mentioned that magnetic nanoparticles utilized in biomedical applications need to possess particular, complicated characteristics. Surfactant molecules coating the nanoparticles can provide a new platform for further modification, broadening the scope of such nanosystems into biomedical applications while also providing colloidal stability and biocompatibility [ 46 , 47 ].…”