Herein, the Fe3O4 particles synthesized with the assistance of EDTA were also intrinsically stabilized with a layer of hydrophilic ligand in situ, which was Trichostatin A nmr essential for their long-term stability in aqueous media without any surface modification. Methods Synthesis of Fe3O4 particles In a typical synthesis of 725 nm Fe3O4 particles, 1.3 g of anhydrous FeCl3 was first vigorously mixed with 40 mL of ethylene glycol (EG) to form a clear solution. Then, 0.47 g of EDTA was added and the mixture was heated at 110°C, followed by
dissolving of anhydrous sodium acetate (NaOAc) (2.4 g), Then the mixture was transferred into a 100-mL Teflon-lined stainless-steel autoclave and sealed in air. The EPZ004777 research buy autoclave was kept at 200°C for 10 h. The black products were collected by a magnet and washed with ethanol three times, and the products were dried at 60°C for further use. Characterizations The x-ray diffraction (XRD) patterns were collected between 20° and 80° (2θ) on an x-ray diffraction system (X’Pert Pro, PANalytical Co., Almelo, The Netherlands) with a graphite monochromator and Cu Kα radiation (λ = 0.15406 nm). Transmission electron microscope (TEM) images and selected area electron diffraction (SAED) patterns were obtained (JEOL JEM-2100; JEOL, Tokyo, Japan) operated at an accelerating voltage of 200 kV. The samples for TEM and high-resolution transmission electron microscope (HR-TEM) analyses were prepared
by spreading a drop of as-prepared magnetite nanoparticle-diluted dispersion on copper grids coated with a carbon film followed by evaporation
under ambient conditions. Atom force microscope (AFM) characterization was carried out using Scan Asyst-Air (Bruker Multimode 8, Bruker Corporation, Billerica, MA, USA). Measurements were carried out in air, and imaging was performed in tapping mode. The height, amplitude, and phase images were recorded. The scanning electron microscopy (SEM) images were obtained using LEO 1530 microscope (LEO, Munich, Germany). Results and discussion The morphology of the as-prepared Amrubicin Fe3O4 particles was characterized by SEM (Figure 1). As shown in Figure 1A, when FeCl3 selleckchem concentration is low (0.05 mol L−1), the products are nonuniform, consisting of spherical nanocrystal clusters and small nanocrystal aggregations. However, when the FeCl3 concentration is in the range of 0.10 to 0.20 mol L−1, all of Fe3O4 particles have a nearly spherical shape (Figure 1B,C). The diameters of the particles slightly increase from 622 ± 145 nm to 717 ± 43 nm, but their sizes become more uniform with the increase of FeCl3 concentration, indicating that higher FeCl3 concentrations could lead to a larger and more uniform particle size. Figure 1 TEM images of Fe 3 O 4 particles synthesized with different FeCl 3 concentrations. (A) 0.05. (B) 0.10. (C) 0.20 mol L−1. Inset is the corresponding particle size distribution.