Study On The Synthetic Method And Properties Of Hyperbranched Glycidol Grafted Magnetic Nanoparticles

Magnetic Fe3O4 nanoparticles with special physical and chemical properties, in the field of research nano-materials preparation and application of Fe3O4 nano-particles has gain more and more attention and became a new hotspot. Futhermore,due to their outstanding bio-inert and modifiable surfaces, hyperbranched polyglycerol-grafted Fe3O4 nanoparticles(HPG-grafted MNPs) have been extensively studied,in this paper the synthesis methods and the potential medcial applications were studied on the HPG-grafted MNPs as a kind of new contrast agent of magnetic resonance imaging(MRI). HPG-grafted MNPs were successfully synthesized via a facile one-pot reaction using acetylacetone iron, iron oxalate as the precursor. Size-differing HPG-grafted MNPs can be obtained through tuning the initial concentration of precursor. Surface chemical state and core crystalline form of HPG-grafted MNPs were characterized by X-ray photoelectron spectroscopy(XPS) and X-ray diffraction(XRD), respectively. Organic components of HPG-grafted MNPs, molecular weight of HPG,chemical structure of HPG were respectively characterized by thermal gravimetric analysis(TGA), gel permeation chromatography(GPC), and 1 H NMR. The size, morphology, of the nanoparticles were observed by TEM. The hydrodynamic size of the nanoparticles were determined by dynamic Light Scattering(DLS), it can be concluded that the HPG-grafted MNPs are highly dispersible in aqueous media, such as cell culture medium and fetal bovine serum(FBS). The as-synthesized HPG-grafted MNPs with a core size of 8 nm can be well dispersed in water at a high concentration of 45 mg/m L. In vitro MTT assays confirmed that the HPG-grafted MNPs did not possess significant toxicity towards macrophages and 3T3 fibroblasts. The magnetic properties of HPG-grafted MNPs were characterized by a vibrating sample magnetometer(VSM) and the results showed that HPG-grafted MNPs has a higher saturation magnetic flux and is superparamagnetic. Futhermore,the size effect of HPG-grafted MNPs was investigated on Ms, transverse relaxation(R2)and R2/R1 ratio,cytotoxicity, and cell uptake, Finally, we conducted a preliminary in vivo magnetic resonance imaging(MRI) experiment of the nanoparticles to observe the distribution and the ability to be a MRI contrast agent in a rabbit.