Gold Nanoparticles:  Assembly, Supramolecular Chemistry, Quantum-Size-Related Properties, and Applications toward Biology, Catalysis, and Nanotechnology

Daniel, Marie‐Christine; Astruc, Didier

doi:10.1021/cr030698+

Cited by 12,031 publications

(7,330 citation statements)

References 715 publications

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“…According to the plasmon mode coupling theory, the symmetric combination results in lower energy (redshift), while the antisymmetric combination results in higher energy (blueshift). [[qv: 3c,19]] In addition to the major peak, the SAFHs also exhibited a broad shoulder peak in the range of 450–500 nm that may be attributed to the near‐field coupling between the adjacent Ag islands on each heterostructure 20. Compared with the similar sized of pure Ag NPs (Figure S12, Supporting Information), the absorption peaks of both JAFHs and SAFHs exhibited distinct blueshifts (Figure S13a,b, Supporting Information).…”

Section: Resultsmentioning

confidence: 99%

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe₃O₄ Heterostructures with Reduced Cytotoxicity

Zhang

Yang

et al. 2018

Advanced Science

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The unique physicochemical properties of silver nanoparticles offer a large potential for biomedical application, however, the serious biotoxicity restricts their usage. Herein, nanogalvanic couple Ag–Fe@Fe3O4 heterostructures (AFHs) are designed to prevent Ag+ release from the cathodic Ag by sacrificial anodic Fe, which can reduce the cytotoxicity of Ag. AFHs are synthesized with modified galvanic displacement strategy in nonaqueous solution. To eliminate the restriction of lattice mismatch between Fe and Ag, amorphous Fe@Fe3O4 nanoparticles (NPs) are selected as seeds, meanwhile, reductive Fe can reduce Ag precursor directly even at as low as 20 °C without additional reductant. The thickness of the Fe3O4 shell can influence the amorphous properties of AFHs, and a series of Janus‐ and satellite‐like AFHs are synthesized. A “cut‐off thickness” effect is proposed based on the abnormal phenomenon that with the increase of reaction temperature, the diameter of Ag in AFHs decreases. Because of the interphase interaction and the coupling effect of Ag and Fe@Fe3O4, the AFHs exhibit unique optical and magnetic properties. This strategy for synthesis of monodisperse heterostructures can be extended for other metals, such as Au and Cu.

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Section: Resultsmentioning

confidence: 99%

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe₃O₄ Heterostructures with Reduced Cytotoxicity

Zhang

Yang

et al. 2018

Advanced Science

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“…[7][8][9][10] Sub-10 nm nanocrystals demonstrate different physical and chemical properties from large nanocrystals. [11][12][13][14][15][16][17][18] Previous research unambiguously showed that the structure dependency of activity and selectivity are more significant for nanocrystals smaller than 10 nm. [3][4][5] Also, smaller nanocrystals have higher dispersion than larger ones and this fact permits more efficient use of precious metals.…”

Section: Introductionmentioning

confidence: 98%

Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

et al. 2009

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Platinum nanocubes and nanopolyhedra with tunable size from 5 nm to 9 nm were synthesized by controlling the reducing rate of metal precursor ions in a one-pot polyol synthesis. A two-stage process is proposed for the simultaneous control of size and shape.In the first stage, the oxidation state of the metal ion precursors determined the nucleation rate and consequently the number of nuclei. The reaction temperature controlled the shape in the second stage by regulation of the growth kinetics. These well-defined nanocrystals were loaded into MCF-17 mesoporous silica for examination of catalytic properties. Pt loadings and dispersions of the supported catalysts were determined by elemental analysis (ICP-MS) and H 2 chemisorption isotherms, respectively. Ethylene hydrogenation rates over the Pt nanocrystals were independent of both size and shape and comparable to Pt single crystals. For pyrrole hydrogenation, the nanocubes enhanced ring opening ability and thus showed a higher selectivity to n-butylamine compared to nanopolyhedra.

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“…The peak of the d 111 reflection has been deconvoluted to the Lorentzian curve for determining the full width at half-maximum (FMWH) value. The crystalline domain has been calculated from the Debye-Scherrer formula using the FWMH value of the corresponding index peaks giving an average † Ecole Nationale Supérieure 12 Inhibition data of 3a,b, GNP-1/2, the standard, clinically used CAI acetazolamide AZA (5-acetamido-1,3,4-thiadiazole-2-sulfonamide), and Au NPs (Au@) as control, against isoforms hCA I and II (cytosolic isozymes) and the transmembrane, tumor-associated isozyme hCA IX (a construct incorporating the catalytic domain and proteoglycan regions of the enzyme), 13 are shown in Table 1. 14 A stopped-flow method has been used for assaying the CA-catalyzed CO 2 hydration activity with Phenol red as indicator, working at the absorbance maximum 557 nm, following the initial rates of the CA-catalyzed CO 2 hydration reaction for 10-100 s. For each inhibitor at least six traces of the initial 5-10% of the reaction have been used for determining the initial velocity.…”

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confidence: 99%

Carbonic Anhydrase Inhibitor Coated Gold Nanoparticles Selectively Inhibit the Tumor-Associated Isoform IX over the Cytosolic Isozymes I and II

Stiti

Cecchi²,

Rami³

et al. 2008

J. Am. Chem. Soc.

102

106

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The carbonic anhydrases (CAs, EC 4.2.1.1) are ubiquitous metalloenzymes with five independently evolved (R, ,γ,δ,ς) classes reported up to date. [1][2][3] These enzymes catalyze the reversible hydration of carbon dioxide to bicarbonate and protons by means of a metalhydroxide (Lig 3 M 2+ (OH) -) mechanism. 2 In addition to the established role of the carbonic anhydrase inhibitors (CAIs) as diuretics and antiglaucoma drugs, it has recently emerged that CAIs could have potential as novel antiobesity, anticancer, and anti-infective drugs. 1,2 A critical problem in the design of CAIs is related to the high number of isoforms in mammals (15), their diffuse localization in many tissues/organs, and the lack of isozyme selectivity of the presently available inhibitors. [1][2][3][4] Recently, nanoparticles received great attention for their biomedical applications both for the site-specific delivery of drugs 7 or for imaging purposes. 7,8 Several recent such examples include HIV inhibition with a CCR5 antagonist attached to multivalent gold nanoparticles (Au NPs), tumor targeting with NPs loaded with hydroxycamptothecin, paclitaxel, or fumagillin, and magnetic resonance imaging (MRI) techniques of tumors based on integrins targeting with Fe 3 O 4 NPs, computer tomography (CT) or MRI imaging with gadolinium chelate Au NPs, etc. 7,8 Human CA IX (hCA IX) is an extracellular, transmembrane isoform which was recently shown to constitute a novel and interesting target for the anticancer therapy due to its overexpression in many cancer tissues and not in their normal counterparts. 1b,9 Its expression is strongly induced by hypoxia present in many tumor tissues and correlated with a bad response to classical chemo-and radiotherapies. 1b,9 CA IX was shown to acidify the extratumoral medium leading both to the acquisition of metastasic phenotypes and to chemoresistance with many anticancer drugs, these processes being reverted by inhibition of the enzyme catalytic activity with sulfonamide inhibitors. 1b,9 The development of selective CA IX inhibitors might provide useful tools for highlighting the exact role of CA IX in hypoxic cancers, to control the pH imbalance of tumor cells and lead to novel diagnostic or therapeutic applications for the management of such tumors. 1b,9 Although many sulfonamide/sulfamate/sulfamide potent CA IX inhibitors were reported, few of them show an acceptable level of selectivity for inhibiting the transmembrane-tumor associated target isoform IX over the cytosolic, ubiquitous isozymes hCA I and II. 1b,9 Considering the extracellular localization of the target CA isoform and the fact that nanomaterials generally show membrane impermeability, 10 we report here the synthesis of CAI coated Au NPs which show excellent CA IX inhibitory properties and selectivity for the inhibition of the tumor-associated isoform over hCA I and II.The key intermediate 3a was synthesized by coupling lipoic acid 1 with 4-aminoethylbenzene sulfonamide 2a in the presence of EDCI/ DMAP, as outlined in Scheme 1. The CAI coated...

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Gold Nanoparticles: Assembly, Supramolecular Chemistry, Quantum-Size-Related Properties, and Applications toward Biology, Catalysis, and Nanotechnology

Cited by 12,031 publications

References 715 publications

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe₃O₄ Heterostructures with Reduced Cytotoxicity

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe₃O₄ Heterostructures with Reduced Cytotoxicity

Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

Carbonic Anhydrase Inhibitor Coated Gold Nanoparticles Selectively Inhibit the Tumor-Associated Isoform IX over the Cytosolic Isozymes I and II

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Gold Nanoparticles: Assembly, Supramolecular Chemistry, Quantum-Size-Related Properties, and Applications toward Biology, Catalysis, and Nanotechnology

Cited by 12,031 publications

References 715 publications

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe3O4 Heterostructures with Reduced Cytotoxicity

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe3O4 Heterostructures with Reduced Cytotoxicity

Sub-10 nm Platinum Nanocrystals with Size and Shape Control: Catalytic Study for Ethylene and Pyrrole Hydrogenation

Carbonic Anhydrase Inhibitor Coated Gold Nanoparticles Selectively Inhibit the Tumor-Associated Isoform IX over the Cytosolic Isozymes I and II

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Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe₃O₄ Heterostructures with Reduced Cytotoxicity

Galvanic Displacement Synthesis of Monodisperse Janus‐ and Satellite‐Like Plasmonic–Magnetic Ag–Fe@Fe₃O₄ Heterostructures with Reduced Cytotoxicity