A facile, two-step synthesis and characterization of Fe3O4–LCysteine–graphene quantum dots as a multifunctional nanocomposite

Abstract

In this research, a facile, two-step synthesis of Fe 3 O 4 -L Cysteine -graphene quantum dots (GQDs) nanocomposite is reported. This synthesis method comprises the preparation of GQDs via hydrothermal route, which should be conjugated to the L Cysteine functionalized core-shell magnetic structure with the core of about 7.5-nm iron oxide nanoparticle and 3.5-nm L Cysteine shell. L Cysteine, as a biocompatible natural amino acid, was used to link magnetite nanoparticles (MNPs) with GQDs. X-ray powder diffraction, Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, energy dispersive X-ray were used to investigate the presence and formation of MNPs, L Cysteine functionalized MNPs, and final hybrid nanostructure. Morphology and size distribution of nanoparticles were demonstrated by scanning electron microscopy and transmission electron microscopy. Finally, the magnetic and optical properties of the prepared nanocomposite were measured by vibrating sample magnetometer, ultraviolet-visible, and photoluminescence spectroscopy. The results show that Fe 3 O 4 -L Cysteine -GQDs nanocomposite exhibits a superparamagnetic behavior at room temperature with high saturation magnetization and low magnetic coercivity, which are 28.99 emu/g and 0.09 Oe, respectively. This nanocomposite also shows strong and stable emission at 460 nm and 530 nm when it is excited with the 235 nm wavelength. The magnetic GQDs structure also reveals the absorption wavelength at 270 nm. Therefore, Fe 3 O 4 -L Cysteine -GQDs nanocomposite can be considered as a potential multifunctional hybrid structure with magnetic and optical properties simultaneously. This nanocomposite can be used for a wide range of biomedical applications like magnetic resonance imaging (MRI) contrast agents, biosensors, photothermal therapy, and hyperthermia.

A Comprehensive Review of Graphitic Carbon Nitride (g-C3N4)–Metal Oxide-Based Nanocomposites: Potential for Photocatalysis and Sensing

“…Iron oxides have many applications in different area such as biomedical applications, environmental application, etc. [214,215]. Wang et al prepared g-C 3 N 4 -Fe 2 O 3 nanocomposite via chemical co-precipitation approach [209].…”

A critical review of bioceramics for magnetic hyperthermia

“…29,30 The physics of resin flow into a mold under pressure is similar to the seepage problem and so similar approaches have been used also to model the flow of resin into a mold containing fiber mats. 23,[31][32][33][34][35][36][37][38] The models are used in these cases to determine the resin flow front and mold filling times corresponding to different infiltration conditions.…”

“…34,35 Several modification agents, such as amino acids, folic acid, and polyethylene glycol (PEG), are used to functionalize MNPs via surface treatment, thus shelling the magnetic core with more biologically compatible materials. [34][35][36][37][38] Magnetic properties like coercive force (H c ), remnant magnetization (M r ), and saturation magnetization (M s ) are greatly influenced by size, shape, and surface coating. Due to the core-shell interface and shielding effects of the modification layer, the magnetic properties of the pristine sample will be decreased.…”

“…29,30 The physics of resin under pressure is similar to the seepage pr lar approaches have been used also to mod into a mold containing fiber mats. 23,[31][32][33][34][35][36][37][38] T in these cases to determine the resin flow ing times corresponding to different infilt Preceramic polycarbosilane polymers as precursors to make ceramic fibers 10,3 trix. [7][8][9]40,41 A survey of the published literature shows that process modeling of CMCs has been studied by a number of researchers.…”

Sustainable magnetically recoverable Iridium-coated Fe3O4 nanoparticles for enhanced catalytic reduction of organic pollutants in water

“…We have decided to exploit this strategy further by immobilization of Iridium metal on the surface of tryptophan (AA) grafted Fe 3 O 4 nanoparticles. We anticipate that tryptophan AA anchored on the surface of Fe 3 O 4 will enhance the stability of magnetic nanoparticles towards surface oxidation, and e ciently reduce the agglomeration of iridium nanoparticles (Dhanalakshmi et al 2020;Alaghmandfard and Madaah Hosseini 2021;Belachew et al 2021). The Iridium NPs as photocatalysts for various redox reactions is well known (Babajani and Jamshidi 2019;Dhanalakshmi et al 2020).…”