The Experts below are selected from a list of 40260 Experts worldwide ranked by ideXlab platform
Wolfgang J. Parak - One of the best experts on this subject based on the ideXlab platform.
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Optical Sensing of Small Ions with Colloidal Nanoparticles
Chemistry of Materials, 2012Co-Authors: Dorleta Jimenez De Aberasturi, Jose-maria Montenegro, Idoia Ruiz De Larramendi, Teofilo Rojo, Thomas A. Klar, Ramon A. Alvarez-puebla, Luis M. Liz-marzán, Wolfgang J. ParakAbstract:Colloidal Nanoparticles, in particular gold Nanoparticles and quantum dots, can be used in a variety of different assays for optical sensing of small ions in solution. In this review, different detection principles are introduced and their potential use for detection in biological samples (such as intracellular sensing) is discussed.
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size determination of bio conjugated water soluble Colloidal Nanoparticles a comparison of different techniques
Journal of Physical Chemistry C, 2007Co-Authors: Ralph A Sperling, Tim Liedl, Stefan Duhr, Stefan Kudera, Marco Zanella, Walter H Chang, Dieter Braun, Wolfgang J. ParakAbstract:The size of inorganic Colloidal Nanoparticles coated with organic layers of different thickness has been measured with different techniques, including transmission electron microscopy, gel electrophoresis, size exclusion chromatography, fluorescence correlation spectroscopy, and thermophoresis. The results are critically compared, and the advantages and disadvantages of the respective methods are discussed.
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on the development of Colloidal Nanoparticles towards multifunctional structures and their possible use for biological applications
Small, 2004Co-Authors: Teresa Pellegrino, Tim Liedl, Stefan Kudera, Almudena Munoz Javier, Liberato Manna, Wolfgang J. ParakAbstract:In this Review, we describe the synthesis of high-quality Colloidal Nanoparticles in organic solvents, the mechanisms by which they can be transferred into aqueous solution, and some of their applications in biology. In particular, we will place emphasis on the creation of multifunctional Nanoparticles or nanoparticle assemblies.
Adriano Bigotto - One of the best experts on this subject based on the ideXlab platform.
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SERS study of the adsorption of 2-mercaptobenzoxazole on gold Colloidal Nanoparticles
Journal of Molecular Structure, 2008Co-Authors: Barbara Pergolese, Maurizio Muniz-miranda, Adriano BigottoAbstract:The adsorption of 2-mercaptobenzoxazole on gold Colloidal Nanoparticles has been studied by means of Surface Enhanced Raman Scattering (SERS). SERS data have been interpreted with the help of DFT calculations on models of the ligand bound to gold adclusters. It was found that 2-mercaptobenzoxazole was adsorbed on the Au surface as thiolate through the sulphur and nitrogen atoms. The molecular plane assumes a tilted orientation with respect to the gold surface.
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Surface enhanced Raman spectroscopic studies on 1H-1,2,4-triazole adsorbed on silver Colloidal Nanoparticles
Vibrational Spectroscopy, 2008Co-Authors: Barbara Pergolese, Maurizio Muniz-miranda, Adriano BigottoAbstract:Abstract 1H-1,2,4-triazole is a very effective corrosion inhibitor for copper. The adsorption of this compound on silver Colloidal Nanoparticles has been studied by means of surface enhanced Raman scattering (SERS). SERS data are interpreted with the help of DFT calculations of models of the surface complex formed by 1H-1,2,4-triazole on the silver Colloidal Nanoparticles surface. It was found that this compound is adsorbed on metal surface in its anionic form and that it interacts with silver through the N 1 and N 2 atoms. The molecular plane assumes a tilted orientation with respect to the silver surface.
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Surface-enhanced Raman scattering investigation of the adsorption of 2-mercaptobenzoxazole on smooth copper surfaces doped with silver Colloidal Nanoparticles.
The journal of physical chemistry. B, 2006Co-Authors: Barbara Pergolese, Maurizio Muniz-miranda, Adriano BigottoAbstract:The adsorption of 2-mercaptobenzoxazole on copper has been investigated by means of surface-enhanced Raman scattering (SERS) by doping smooth copper surfaces with silver Colloidal Nanoparticles. The metal surfaces have been characterized by means of atomic force microscopy measurements. The compound adsorbs on the Cu/Ag surfaces in its ionized thiolic form, adopting a tilted orientation with respect to the metal surface. The anion is chemisorbed through the sulfur and nitrogen atoms on the smooth copper surface, and the silver Colloidal Nanoparticles only enhance the Raman signal due to the electromagnetic mechanism. SERS data have been interpreted with the help of DFT calculations on models of the ligand bound to copper adclusters.
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SERS studies of the adsorption of guanine derivatives on gold Colloidal Nanoparticles.
Physical chemistry chemical physics : PCCP, 2005Co-Authors: Barbara Pergolese, Alois Bonifacio, Adriano BigottoAbstract:Surface enhanced Raman scattering spectra of guanine, guanosine and 2′-deoxyguanosine adsorbed on gold Colloidal Nanoparticles were obtained. From the striking similarity of the SERS spectra of these compounds, it can be evidenced that guanosine and 2′-deoxyguanosine adsorb on gold Nanoparticles through the guanine moiety. The molecular sites involved in the interaction with the gold surface are the same for the 3 compounds: the oxygen of the carbonilic group and the N7 atom. Guanine, guanosine and 2′-deoxyguanosine adsorb on the gold substrates with a tilted orientation with respect to the metal surface. SERS data were interpreted taking into account density functional theoretical (DFT) calculations of guanine.
Maurizio Muniz-miranda - One of the best experts on this subject based on the ideXlab platform.
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SERS study of a tetrapeptide based on histidine and glycine residues, adsorbed on copper/silver Colloidal Nanoparticles
Journal of Raman Spectroscopy, 2014Co-Authors: Cristina Gellini, Giuseppina Sabatino, Anna Maria Papini, Maurizio Muniz-mirandaAbstract:Surface-enhanced Raman scattering has been employed to characterize the adsorption of an oligopeptide containing histidine residues on Colloidal Nanoparticles of metals as Ag and Cu obtained by laser ablation. The title molecule consists of two histidine and glycine residues alternating along the chain and terminating with an acetyl on one side and an amide group on the other. Histidine residues are found to act as docking sites of the molecule to the surface of the metal Nanoparticles. Semiempirical parameterized model number 3 (PM3) calculations performed on molecule/metal model complexes suggest possible different adsorption geometries depending on the metallic substrate. This investigation could provide useful information to address the interaction of protein systems with metal ions, which is often related to fundamental biological process in living systems and can play an important role in different neuropathological diseases. Copyright © 2014 John Wiley & Sons, Ltd.
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SERS study of the adsorption of 2-mercaptobenzoxazole on gold Colloidal Nanoparticles
Journal of Molecular Structure, 2008Co-Authors: Barbara Pergolese, Maurizio Muniz-miranda, Adriano BigottoAbstract:The adsorption of 2-mercaptobenzoxazole on gold Colloidal Nanoparticles has been studied by means of Surface Enhanced Raman Scattering (SERS). SERS data have been interpreted with the help of DFT calculations on models of the ligand bound to gold adclusters. It was found that 2-mercaptobenzoxazole was adsorbed on the Au surface as thiolate through the sulphur and nitrogen atoms. The molecular plane assumes a tilted orientation with respect to the gold surface.
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Surface enhanced Raman spectroscopic studies on 1H-1,2,4-triazole adsorbed on silver Colloidal Nanoparticles
Vibrational Spectroscopy, 2008Co-Authors: Barbara Pergolese, Maurizio Muniz-miranda, Adriano BigottoAbstract:Abstract 1H-1,2,4-triazole is a very effective corrosion inhibitor for copper. The adsorption of this compound on silver Colloidal Nanoparticles has been studied by means of surface enhanced Raman scattering (SERS). SERS data are interpreted with the help of DFT calculations of models of the surface complex formed by 1H-1,2,4-triazole on the silver Colloidal Nanoparticles surface. It was found that this compound is adsorbed on metal surface in its anionic form and that it interacts with silver through the N 1 and N 2 atoms. The molecular plane assumes a tilted orientation with respect to the silver surface.
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Surface-enhanced Raman scattering investigation of the adsorption of 2-mercaptobenzoxazole on smooth copper surfaces doped with silver Colloidal Nanoparticles.
The journal of physical chemistry. B, 2006Co-Authors: Barbara Pergolese, Maurizio Muniz-miranda, Adriano BigottoAbstract:The adsorption of 2-mercaptobenzoxazole on copper has been investigated by means of surface-enhanced Raman scattering (SERS) by doping smooth copper surfaces with silver Colloidal Nanoparticles. The metal surfaces have been characterized by means of atomic force microscopy measurements. The compound adsorbs on the Cu/Ag surfaces in its ionized thiolic form, adopting a tilted orientation with respect to the metal surface. The anion is chemisorbed through the sulfur and nitrogen atoms on the smooth copper surface, and the silver Colloidal Nanoparticles only enhance the Raman signal due to the electromagnetic mechanism. SERS data have been interpreted with the help of DFT calculations on models of the ligand bound to copper adclusters.
Bing Yan - One of the best experts on this subject based on the ideXlab platform.
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Amorphous RE–Fe–B–Na Colloidal Nanoparticles: High temperature solution synthesis and magnetic properties
Materials Research Bulletin, 2015Co-Authors: Li-ping Jia, Bing YanAbstract:Graphical abstract: RE–Fe–B–Na (RE = Nd–Er) Colloidal Nanoparticles by high-temperature solution synthesis are ultra-small monodisperse and air-stable amorphous, whose size and magnetic dependence are studied. - Highlights: • RE–Fe–B–Na Nanoparticles are obtained by high-temperature solution synthesis. • These Colloidal Nanoparticles are monodisperse and size controlled. • The magnetism dependence and possible magnetic coupling mechanism are studied. - Abstract: RE–Fe–B–Na (RE = Nd–Er) Colloidal Nanoparticles are prepared by high-temperature solution synthesis. These Nanoparticles are ultra-small monodisperse, air-stable and amorphous, whose particle size and magnetic property are characterized by transmission electron microscope and superconducting quantum interference device. Taking Nd–Fe–B–Na nanoparticle as an example, it is found that the particle size can be controlled in less than 7 nm. Besides, the magnetic properties of RE–Fe–B–Na Colloidal Nanoparticles can be compared for different rare earth elements. Based on the bulk ferromagnetic coupling, other possible magnetic coupling mechanism is discussed.
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Magnetic amorphous RE–Co–B–Na Colloidal Nanoparticles with high critical temperature
Colloids and Interface Science Communications, 2015Co-Authors: Li-ping Jia, Qiang Zhang, Bing YanAbstract:Abstract High temperature solution synthesis is afforded to the preparation of RE–Co–B–Na Colloidal Nanoparticles with particle size of 20 nm. It is interesting that the critical temperature (T C ) of Sm–Co–B–Na nanoparticle with 20 nm is high, up to over 400 K, for which the possible magnetic coupling mechanism is discussed.
Benoit Denizot - One of the best experts on this subject based on the ideXlab platform.
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Synthesis of small-sized rhenium sulfide Colloidal Nanoparticles
Journal of colloid and interface science, 2007Co-Authors: Benoit DenizotAbstract:Rhenium sulfide Colloidal Nanoparticles with average size 5.5 nm were synthesized. Characterizations by ultraviolet–visible spectrophotometry, transmission electron microscopy, energy dispersive X-ray spectrum, and X-ray powder diffraction verified the formation of ReS2 rhenium sulfide Colloidal Nanoparticles. The Colloidal Nanoparticles had good stability and they could be stored stably for 1 week in water. Surface modification by organic molecules improved the stability of the rhenium sulfide Nanoparticles. The small-sized rhenium sulfide Nanoparticles may be useful for their promising applications in tracing diagnosis and therapy of tumor diseases.