Functionalization of Fe3O4 NPs by Silanization: Use of Amine (APTES) and Thiol (MPTMS) Silanes and Their Physical Characterization

Abstract

In this paper the results concerning the synthesis of magnetite (Fe3O4) nanoparticles (NPs), their functionalization using silane derivatives, such as (3-Aminopropyl)triethoxysilane (APTES) and (3-mercaptopropyl)trimethoxysilane (MPTMS), and their exhaustive morphological and physical characterization by field emission scanning electron microscopy (FE-SEM) with energy dispersion X-ray spectrometer (EDX) analysis, AC magnetic susceptibility, UV-VIS and IR spectroscopy, and thermogravimetric (TGA) analyses are reported. Two different paths were adopted to achieve the desired functionalization: (1) the direct reaction between the functionalized organo-silane molecule and the surface of the magnetite nanoparticle; and (2) the use of an intermediate silica coating. Finally, the occurrence of both the functionalization with amino and thiol groups has been demonstrated by the reaction with ninhydrin and the capture of Au NPs, respectively.

Fabrication and Cytotoxicity of Gemcitabine-Functionalized Magnetite Nanoparticles

“…This supplementary threshold may be due to the degradation of hydroxyl groups on the surface of the nanoparticles [23]. Similarly, Villa et al [24] have reported a two-step degradation of aminopropyltrietoxysilane (APTES) linked to the surface of Fe 3 O 4 nanoparticles. Here, for Fe 3 O 4 , a weight reduction of 3.3% was obtained and for Fe 3 O 4 @GEM 10.1%, from which 6.8% is due to the degradation of GEM.…”

Green synthesis of Au decorated CoFe2O4 nanoparticles for catalytic reduction of 4-nitrophenol and dimethylphenylsilane oxidation

“…A quick comparison with FTIR spectra of APTES allows identifying the presence of intense peaks at 1100 cm À1 and 770 cm À1 corresponding to Si-O and Si-O-C, respectively. 26 Furthermore, two additional stretching vibration bands associated to N-C at 1390 cm À1 and C-H at 3000 cm À1 were observed. 27 These results suggest the successful functionalization of CoFe 2 O 4 , which agrees with the successful attachment of Au NPs observed in Fig.…”

Nano-Fe3O4@SiO2-supported boron sulfonic acid as a novel magnetically heterogeneous catalyst for the synthesis of pyrano coumarins

“…The structures of the obtained products 4 and 6 were deduced from their elemental analysis, IR, 1 H, and 13 C NMR spectroscopy and they were compared with authentic samples. [40][41][42] Although both electron-rich and electron-poor aldehydes afforded the desired products 4 and 6, aldehydes having electron-withdrawing groups in comparison with those having electron-donating ones performed this transformation in better yields.…”

“…Melting points were determined by an electrothermal KSB1N apparatus and are uncorrected. The NMR spectra of 1 H in DMSO were recorded on a Bruker Avance Ultra Shield 400 MHz spectrometer, and 13 C NMR spectra were recorded at 100 MHz using TMS as an internal standard. Infrared (IR) spectra were obtained with a JASCO Fourier transform-infrared (FT-IR)/680 spectrometer using KBr pellets.…”

“…[10][11][12] A protective shell of silica as a coating can be formed on the surface of Fe 3 O 4 nanoparticles to prevent them from oxidizing in an air atmosphere, provide simple surface functionalization, and enable aggregation between particles. 13,14 Boron sulfonic acid, as a solid acid catalyst that was rst introduced by Kiasat et al, and silica boron sulfonic acid have many advantages such as simplicity in preparation, availability of precursor, economically benign, non-toxicity, and high activity/ selectivity with excellent yields in various chemical processes. 15 Synthesis of hybrid heterocycles that contain biologically active skeletons is an interesting subject in organic synthesis.…”