Gold-Coated Cobalt Ferrite Nanoparticles via Methionine-Induced Reduction

Mikalauskaitė, Agnė; Kondrotas, Rokas; Niaura, Gediminas; Jagminas, Arūnas

doi:10.1021/acs.jpcc.5b03528

Cited by 33 publications

(38 citation statements)

References 49 publications

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“…The resulting core–shell MNPs were soluble in water, and their magnetic properties were not degraded. Another solution deposition method for gold on MNPs is the one‐pot reduction of AuCl 4 – with methionine, which has been performed on CoFe 2 O 4 NPs . Gold coated NPs open the door for the use of small molecule and biomolecule‐based thiol functionalization of NPs …”

Section: Np Coatingsmentioning

confidence: 99%

Nanostructured Soft Matter with Magnetic Nanoparticles

Tokarev

Yatvin

Trotsenko

et al. 2016

Adv Funct Materials

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3761wileyonlinelibrary.com single magnetic domain of the particle. The mean time between fl ips (the Neel relaxation time) depends on temperature. For many practical applications, the time of the experiment is orders of magnitude longer than the Neel relaxation time, so that the average particle magnetization is zero. The random fl ipping depends on temperature. At a given (generally low) temperature (termed the blocking temperature) the Neel relaxation time is the same as the characteristic time of the experiment, and thus above the blocking temperature the nanoparticle is superparamagnetic. The blocking temperature depends on the particle composition, size and shape. For example, for a 10 nm diameter spherical Fe 3 O 4 nanoparticle in a typical laboratory experiment the blocking temperature is far below 200 K, [ 2 ] thus the particles are superparamagnetic for most intended applications. Very low toxicity, low cost, simple and well-reproducible synthesis render iron oxide nanoparticles the most extensively used superparamagnetic nanomaterial.The response of a superparamagnetic particle to a magnetic fi eld and the experimental timeframe required for loss of the average magnetization has been intensively explored in numerous examples of stimuli-responsive nanostructures. The major advantage of materials based on magnetic particles is that the mechanism of response does not interfere with many other properties of the materials and that the magnetic fi eld (with a practical range on the order of 1 Tesla or less) is noninvasive for living organisms. The latter is a critical aspect for biomedical and other applications involving live species. The number of annual publications that utilize superparamagnetic nanoparticles is >1000 and rising. The rapid increase of interest in magnetic nanoparticles (MNPs) can be attributed to studies on magnetic imaging and drug delivery systems which built upon older research involving ferrofl uids. A number of excellent reviews have recently been published on the synthesis and applications of MNPs, [ 3 ] surface functionalization, [ 4 ] their biomedical applications, [ 3b , 5 ] applications in recyclable catalysts, [ 6 ] MNP toxicity, [ 7 ] and many others. [ 8 ] This review is focused on the surface functionalization of MNPs that can be used to either (a) generate nanostructured materials or to (b) add responsive properties to the materials. The goal of this review is to assemble the most practical and important information for material scientists working in the area of nanostructured materials with a focus on assembly using bottom-up methods. Magnetic fi eld induced forces can be tuned by the regulation of the magnetic fi eld direction, strength and gradient, which provide a large toolbox for the manipulation of nanoscale forces. [ 9 ] The structure of this article is as Magnetic fi eld imaging in living specimens with magnetic nanoparticles as contrasting agents has attracted signifi cant interest in the rapidly developing fi eld of nanomedicine. Developments in this fi eld ...

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Section: Np Coatingsmentioning

confidence: 99%

Nanostructured Soft Matter with Magnetic Nanoparticles

Tokarev

Yatvin

Trotsenko

et al. 2016

Adv Funct Materials

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“…[1][2][3][4][5][6][7][8][9][10][11][12] Currently, nanoparticles and nano-architectures of CFO-based materials are gaining tremendous interest in view of their ability to exhibit tunable electrical and magnetic properties, which could be exploited in numerous technological applications. 2,3,8,10 Furthermore, higher values of magnetostriction make CFO a potential candidate material for 'strain sensor and actuator' applications. 11 Cobalt ferrites can be combined with a piezoelectric/ferroelectric material resulting in the multiferroic/magnetoelectric hetero-structures for application in multifunctional and tunable magneto-electronic devices.…”

Section: Introductionmentioning

confidence: 99%

Effect of Molybdenum Incorporation on the Structure and Magnetic Properties of Cobalt Ferrite

et al. 2017

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Melendez, A.; Manadhar, S.; Singamaneni, S. R.; Reddy, Kongara M.; Gandha, Kinjal H.; Niebedim, I. C.; and Ramana, C. V., "Effect of Molybdenum Incorporation on the Structure and Magnetic Properties of Cobalt Ferrite" (2017). Ames Laboratory Accepted Manuscripts. 61. AbstractWe report on the effect of molybdenum (Mo) incorporation on the crystal structure, surface morphology, Mo chemical valence state, and magnetic properties of cobalt ferrite (CoFe2O4, referred to CFO). Molybdenum incorporated cobalt ferrite (CoFe2-xMoxO4, referred to CFMO) ceramics were prepared by the conventional solid-state reaction method by varying the Mo concentration in the range of x = 0.0-0.3. X-ray diffraction studies indicate that the CFMO materials crystallize in inverse spinel cubic phase. Molybdenum incorporation induced lattice parameter increase from 8.322 to 8.343 Å coupled with a significant increase in density from 5.4 to 5.7 g/cm3 was evident in structural analyses. Scanning electron microscopy imaging analyses indicate that the Mo incorporation induces agglomeration of particles leading to larger particle size with increasing x(Mo) values. Detailed X-ray photoelectron spectroscopic (XPS) analyses indicate the increasing Mo content with increasing x from 0.0 to 0.3. XPS confirms that the chemistry of Mo is complex in these CFMO compounds; Mo ions exist in the lower oxidation state (Mo4+) for higher x while in a mixed chemical valence state (Mo4+, Mo5+, Mo6+) for lower x values. From the temperature-dependent magnetization, the samples show ferrimagnetic behavior including the pristine CFO. From the isothermal magnetization measurements, we find almost 2-fold decrease in coercive field (Hc) from 2143 to 1145 Oe with the increase in Mo doping up to 30%. This doping-dependent Hc is consistently observed at all the temperatures measured (4, 100, 200, and 300 K). Furthermore, the saturation magnetization estimated at 4 K and at 1.5 T (from M-H loops) goes through a peak at 92 emu/g (at 15% Mo doping) from 81 emu/g (pristine CFO), and starts decreasing to 79 emu/g (at 30% Mo doping). The results demonstrate that the crystal structure, microstructure, and magnetic properties can be tuned by controlling the Mo-content in the CFMO materials. ABSTRACTWe report on the effect of molybdenum (Mo) incorporation on the crystal structure, surface morphology, Mo chemical valence state and magnetic properties of cobalt ferrite (CoFe2O4, referred to CFO). Molybdenum incorporated cobalt ferrite (CoFe2-xMoxO4, referred to CFMO) ceramics were prepared by the conventional solid-state reaction method by varying the Mo concentration in the range of x=0.0-0.3. X-ray diffraction studies indicate that the CFMO materials crystallize in inverse spinel cubic phase. Molybdenum incorporation induced lattice parameter increase from 8.322 to 8.343 Å coupled with a significant increase in density from 5.4 to 5.7 g/cm 3 was evident in structural analyses. Scanning electron microscopy imaging analysis indicate that the Mo incorporation induces agglomeration of pa...

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“…The formation of a gold shell on magnetite (Fe 3 O 4 ) or ferrite surfaces through reduction of chloroauric acid by citrates or borohydride is usually problematic due to the formation of pure gold crystallites in the solution [ 5 , 15 ]. The deposition of gold onto the surface of magnetic iron oxide-based NPs can also be achieved via their impregnation with hydroxylamine [ 16 ], vitamin C [ 17 ] or methionine [ 18 – 19 ], which are capable to reduce the gold ions at the surface of NPs. However, in this case, uniform coating of magnetic NPs can only be obtained via precise control of the precursor content and all steps of the multistep process [ 17 – 18 ].…”

Section: Introductionmentioning

confidence: 99%

“…The deposition of gold onto the surface of magnetic iron oxide-based NPs can also be achieved via their impregnation with hydroxylamine [ 16 ], vitamin C [ 17 ] or methionine [ 18 – 19 ], which are capable to reduce the gold ions at the surface of NPs. However, in this case, uniform coating of magnetic NPs can only be obtained via precise control of the precursor content and all steps of the multistep process [ 17 – 18 ]. As a result, this way is time-consuming and it does not fully prevent the formation of gold crystallites in the plating solution.…”

Section: Introductionmentioning

confidence: 99%

Methionine-mediated synthesis of magnetic nanoparticles and functionalization with gold quantum dots for theranostic applications

Jagminas¹,

Mikalauskaitė²,

Karabanovas

et al. 2017

Beilstein J. Nanotechnol.

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Biocompatible superparamagnetic iron oxide nanoparticles (NPs) through smart chemical functionalization of their surface with fluorescent species, therapeutic proteins, antibiotics, and aptamers offer remarkable potential for diagnosis and therapy of disease sites at their initial stage of growth. Such NPs can be obtained by the creation of proper linkers between magnetic NP and fluorescent or drug probes. One of these linkers is gold, because it is chemically stable, nontoxic and capable to link various biomolecules. In this study, we present a way for a simple and reliable decoration the surface of magnetic NPs with gold quantum dots (QDs) containing more than 13.5% of Au+. Emphasis is put on the synthesis of magnetic NPs by co-precipitation using the amino acid methionine as NP growth-stabilizing agent capable to later reduce and attach gold species. The surface of these NPs can be further conjugated with targeting and chemotherapy agents, such as cancer stem cell-related antibodies and the anticancer drug doxorubicin, for early detection and improved treatment. In order to verify our findings, high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), FTIR spectroscopy, inductively coupled plasma mass spectroscopy (ICP-MS), and X-ray photoelectron spectroscopy (XPS) of as-formed CoFe2O4 NPs before and after decoration with gold QDs were applied.

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Gold-Coated Cobalt Ferrite Nanoparticles via Methionine-Induced Reduction

Cited by 33 publications

References 49 publications

Nanostructured Soft Matter with Magnetic Nanoparticles

Nanostructured Soft Matter with Magnetic Nanoparticles

Effect of Molybdenum Incorporation on the Structure and Magnetic Properties of Cobalt Ferrite

Methionine-mediated synthesis of magnetic nanoparticles and functionalization with gold quantum dots for theranostic applications

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