Preparation, characterization and dynamical mechanical properties of dextran-coated iron oxide nanoparticles (DIONPs)

Abstract

Dextran-coated iron oxide nanoparticles (DIONPs) with appropriate surface chemistry exhibit many interesting properties that can be exploited in a variety of biomedical applications such as magnetic resonance imaging (MRI) contrast enhancement, tissue repair, hyperthermia, drug delivery and in cell separation. This paper reports the experimental detail for preparation, characterization and investigation of thermal and dynamical mechanical characteristics of the dextran-coated FeO magnetic nanoparticles. In our work, DIONPs were prepared in a 1:2 ratio of Fe(II) and Fe(III) salt in the HCl solution with NaOH at given temperature. The obtained dextran-coated iron-oxide nanoparticles structure-property correlation was characterized by spectroscopic methods; attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and XRD. Coating dextran on the iron-oxide proof of important peaks can be seen from the ATR-FTIR. Dramatic crystallinity increment can be observed from the XRD pattern of the iron-oxide dextran nanoparticles. The thermal analysis was examined by differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA) and differential thermal analysis (DTA). Dynamical mechanical properties of dextran nanoparticles were analysed by dynamic mechanical analysis (DMA). Thermal stability of the iron oxide dextran nanoparticles is higher than that of the dextran.

Dextran-Thyme Magnesium-Doped Hydroxyapatite Composite Antimicrobial Coatings

“…%) into the HAp lattice [30]. In the case of 10MgHAp-Dex-thyme powder and coating, supplemental IR maxima were evidenced in the spectral regions not superimposed by the more prominent HAp characteristic vibration modes, namely: vibrations of α-(1,3) linkages of glycoside units in dextran (~760-761 cm −1 ) [49][50][51][52][53], out-of-plane wagging vibrations of C-H in thymol units (~818 cm −1 , more evident in the case of the powder) [54][55][56] The FTIR-ATR spectra of simple 10MgHAp powders, 10MgHAp-Dex-thyme powder, and coating are presented comparatively in Figure 10, together with the reference spectra of raw dextran powder and thyme oil. The vibration bands distinctive to a B-type carbonated hydroxyapatite [30,[45][46][47][48] were evidenced for all studied bioceramic-based materials, i.e., ν 4 bending (~558 and~599-600 cm −1 ), ν 1 symmetric stretching (~950-951 cm −1 ), and ν 3 asymmetric stretching (~1004-1013 and~1097-1099 cm −1 ) of (PO 4 ) 3− groups; libration of structural (OH) − units (~630 cm −1 ); and ν 2 bending (~872-873 cm −1 ) and ν 3 asymmetric stretching (~1418-1424 and~1456-1478 cm −1 ) vibrations of (CO 3 ) 2− groups (Figure 10a,b,d,e,g,h).…”

“…%) into the HAp lattice [30]. In the case of 10MgHAp-Dex-thyme powder and coating, supplemental IR maxima were evidenced in the spectral regions not superimposed by the more prominent HAp characteristic vibration modes, namely: vibrations of α-(1,3) linkages of glycoside units in dextran (~760-761 cm −1 ) [49][50][51][52][53], out-of-plane wagging vibrations of C-H in thymol units (~818 cm −1 , more evident in the case of the powder) [54][55][56], vibrations of α-(1,3) linkages of glycoside units in dextran (~918 cm −1 , more evident in the case of the coating) [49][50][51][52], stretching (ν) vibrations of C-O-C covalent bonds and glycosidic bridges in dextran (~1075, 1150-1157 and 1206-1209 cm −1 ) [49][50][51][52], stretching (ν) vibrations of C-O in thyme (~1244 cm −1 ) [54][55][56], bending (δ) vibrations of C-OH in dextran (~1275-1280 cm −1 ) [49][50][51][52], bending (δ) vibration of C-H in dextran (~1348-1350 cm −1 ) [52], and stretching (ν) vibrations of C−H bonds in dextran and thyme (~2889, 2920-2934, 2973-2979 cm −1 ) [50,52,[54][55][56][57]. Only slight peak shifts (of HAp, Dex, and thyme specific IR absorption bands) were noticed in the case of the coating with respect to the blended source powder or raw components.…”

Synthesis and characterization of magnetic nanoparticles of cobalt ferrite coated with silica

“…The cobalt ferrite was prepared by means of the co-precipitation method. The solutions were mixed in the stoichiometric ratio of Co:Fe = 1:2 at pH 13 under mechanical agitation at 700 rpm at different temperatures (27,60, 80 and 98°C). The NaOH solution was used to adjust the pH.…”

“…There are several routes for the synthesis of magnetic nanoparticles of different sizes, such as water-oil microemulsion [25], microwave processing [26], mechanical grinding [27], reverse micelle [28], combustion [29], co-precipitation [30], pyrolysis [31] and among others. The magnetic core of the magnetic nanoparticles can be coated with a polymeric layer of not active sites or anchoring organic molecules to a metal surface [32].…”

Synthesis and Characterization of Water Dispersible Iron Oxide (�a-Fe2O3) Nanoparticles for Biomedical Applications

“…The biopolymers used for the modification of magnetic oxide particles must be biocompatible, biodegradable, non-toxic, non-thrombogenic, non-immunogenic and inexpensive. The most used biopolymers for coating of magnetic oxide particles reported in the literature are: polyethylene glycol (PEG) [23], polyvinyl alcohol (PVA) [24], dextran [25], chitosan [26], polyvinylpyrrolidone (PVP) [27]. Another way to modify the surfaces of magnetic nanoparticles for biomedical applications is by bonding on their surface suitable chemicals that play an important role in the body.…”