Omar Azzaroni

National University of La Plata, Eva Perón, Buenos Aires, Argentina

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Publications (117)638.84 Total impact

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    ABSTRACT: The ability to modulate the surface chemical characteristics of solid-state nanopores is of great interest as it provides the means to control the macroscopic response of nanofluidic devices. For instance, controlling surface charge and polarity of the pore walls is one of the most important applications of surface modification that is very relevant to attain an accurate control over the transport of ions through the nanofluidic architecture. In this work, we describe a new integrative chemical approach to fabricate nanofluidic diodes based on the self-polymerization of dopamine (PDOPA) on asymmetric track-etched nanopores. Our results demonstrate that PDOPA coating is not only a simple and effective method to modify the inner surface of polymer nanopores fully compatible with the fabrication of nanofluidic devices but also a versatile platform for further integration of more complex molecules through different covalent chemistries and self-assembly processes. We adjusted the chemical modification strategy to obtain various configurations of the pore surface: (i) PDOPA layer was used as primer, precursor or even responsive functional coating, (ii) PDOPA layer was used as a platform for anchoring chemical functions via the Michael addition reaction, and (iii) PDOPA was used as a reactive layer inducing the metallization of the pore walls through the in-situ reduction of metallic precursors present in solution. We believe that the transversal concept of integrative surface chemistry offered by polydopamine in combination with the remarkable physical characteristics of asymmetric nanopores constitutes a new framework to design multifunctional nanofluidic devices employing soft chemistry-based nanofunctionalization techniques.
    Journal of the American Chemical Society 04/2015; DOI:10.1021/jacs.5b01638 · 11.44 Impact Factor
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    ABSTRACT: This review presents and discusses recent advances in the emerging field of "gated nanochemistry", outlining the substantial progress made so far. The development of hybrid mesoporous silica with complex tailored pore nanoarchitectures bridges the gap between molecular materials and the requirements of nanodevices for controlled nanoscale chemistry. In the last decade, membranes, particles and thin film porous architectures have been designed, synthesized and selectively modified by molecular, polymeric, organometallic or biologically active groups. The exquisite manipulation of mesopore morphology and interconnection combined with molecular or supramolecular functionalities, and the intrinsic biological compatibility of silica have made these materials a potential platform for selective sensing and drug delivery. The wide répertoire of these hard-soft architectures permit us to envisage sophisticated intelligent nano-systems that respond to a variety of external stimuli such as pH, redox potential, molecule concentration, temperature, or light. Transduction of these stimuli into a predefined response implies exploiting spatial and physico-chemical effects such as charge distribution, steric constraints, equilibria displacements, or local changes in ionic concentration, just to name a few examples. As expected, this "positional mesochemistry" can be only attained through the concerted control of assembly, surface tailoring and, confinement conditions, thus giving birth to a new class of stimuli-responsive materials with modulable transport properties. As a guiding framework the emerging field of "gated nanochemistry" offers methodologies and tools for building up stimuli-sensitive porous architectures equipped with switchable entities whose transport properties can be triggered at will. The gated nanoscopic hybrid materials discussed here not only herald a new era in the integrative design of "smart" drug delivery systems, but also give the reader a perspective of the promising future in the development of mesoporous platforms that can control mass transport on command through the combination of flexible supramolecular routes, with implications on health, environment and energy.
    Chemical Communications 02/2015; DOI:10.1039/c4cc10414e · 6.72 Impact Factor
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    ABSTRACT: Manipulating molecular transport through mesoporous hybrid films is a fascinating approach towards mimicking transport in nature. To understand the details in controlled transport it is necessary to gradually adjust the charge density that in turn results in a precise adjustment of permselectivity. We have created hybrid architectures through the controlled polymerization of a strong polyelectrolyte: (2 methacryloyloxy)-ethyltrimethylammounium (PMETAC) in a mesoporous thin silica film. PMETAC contents from 5 to 100% filling can be obtained by choosing a temperature or light-induced polymerization route, and by varying polymerization times, as proven by ellipso-porosimetry and infrared spectroscopy. Using cyclic voltammetry we demonstrate that a gradual variation of ionic permselectivity from a silanol-regulated to a PMETAC-regulated permselectivity can be obtained by tuning the PMETAC mesopore filling. The resulting behavior ranges from ion exclusion to pre concentration. The experimental observations are correlated with theoretical calculations that provide quantitative insights into the organization of the ions and polymers within the pore. Our findings shed light into the understanding of the interplay between charge density and space on molecular transport, leading towards the rational design of selectively transporting synthetic membranes.
    Chemistry of Materials 01/2015; 27(3). DOI:10.1021/cm5037953 · 8.54 Impact Factor
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    ABSTRACT: Self-organized metallo-supramolecular heterostructures have potential applications that include molecular electronics, photovoltaics, and magnetic devices, among other examples. The main challenge that scientists typically face when designing advanced supramolecular materials is to achieve structurally defined assemblies by resolving conflicting demands on the topological and/or chemical features of the constituting building blocks. Accordingly, the formation of well-defined metallo-supramolecular arrays using ill-defined, highly polydisperse, self-assemblable starting compounds marks a profound departure from traditional supramolecular paradigms. The present work describes the first observation of spontaneous mesophase transformation of well-defined metallo-supramolecular assemblies in solution as a result of the complexation of transition metal ions into the ionophilic domains of highly branched unimolecular micelles constituted of N-acylated hyperbranched polyethylenimine. Experimental results based on a combination of different synchrotron-based techniques provide unprecedented experimental evidence revealing that ion-induced self-assembly of amphiphilic hyperbranched polymers can be used to achieve highly ordered metallo-supramolecular structures not only in solution but also on solid surfaces. We believe that this emerging conceptual framework can open extremely interesting new synthetic and technological opportunities in the area of self-assembly of well-defined metallo-supramolecular architectures obtained from building blocks with poor structural regularity but easily provided in large quantities by simple and inexpensive preparative chemistries.
    ACS Macro Letters 12/2014; 4(1):94-100. DOI:10.1021/mz500688r · 5.24 Impact Factor
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    ABSTRACT: Efficient electrical communication between redox proteins and electrodes is a critical issue in the operation and development of amperometric biosensors. The present study explores the advantages of a nanostructured redox-active polyelectrolyte–surfactant complex containing [Os(bpy)2Clpy]2+ (bpy=2,2′-bipyridine, py= pyridine) as the redox centers and gold nanoparticles (AuNPs) as nanodomains for boosting the electron-transfer propagation throughout the assembled film in the presence of glucose oxidase (GOx). Film structure was characterized by grazing-incidence small-angle X-ray scattering (GISAXS) and atomic force microscopy (AFM), GOx incorporation was followed by surface plasmon resonance (SPR) and quartz-crystal microbalance with dissipation (QCM-D), whereas Raman spectroelectrochemistry and electrochemical studies confirmed the ability of the entrapped gold nanoparticles to enhance the electron-transfer processes between the enzyme and the electrode surface. Our results show that nanocomposite films exhibit five-fold increase in current response to glucose compared with analogous supramolecular AuNP-free films. The introduction of colloidal gold promotes drastic mesostructural changes in the film, which in turn leads to a rigid, amorphous interfacial architecture where nanoparticles, redox centers, and GOx remain in close proximity, thus improving the electron-transfer process.
    Chemistry - A European Journal 10/2014; 20(41). DOI:10.1002/chem.201402707 · 5.70 Impact Factor
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    ABSTRACT: The present study explores the development of mesostructured bioelectrochemical interfaces with accurate compositional and topological control of the supramolecular architecture through the layer-by-layer assembly of ternary systems based on poly(allylamine) containing an osmium polypyridyl complex (OsPA), an anionic surfactant, sodium dodecyl sulfate (SDS) or sodium octodecyl sulfate (ODS), and glucose oxidase (GOx). We show that the introduction of the anionic surfactant allows a sensitive increase of the polyelectrolyte and the enzyme uptake at pH 7.0, enhancing its catalytic behavior in the presence of glucose as compared to the surfactant-free system (OsPA/GOx)n constructed at the same pH. Structural characterization of the multilayer films was performed by means of grazing-incidence small-angle X-ray scattering (GISAXS), which showed the formation of mesostructured domains within the composite assemblies. Experimental results indicate that the balance between ionic and hydrophobic interactions plays a leading role not only in the construction of the self-assembled system but also in the functional properties of the bioactive interface. The structure of the ternary multilayered films depends largely on the length of the alkyl chain of the surfactant. We show that surfactants incorporated into the film also play a role as chemical entities capable of tuning the hydrophobicity of the whole assembly. In this way, the deliberate introduction of short-range hydrophobic forces was exploited as an additional variable to manipulate the adsorption and coverage of protein during each assembly step. However, the integration of long-chain surfactants may lead to the formation of very well-organized interfacial architectures with poor electron transfer properties. This, in turn, leads to a complex trade-off between enzyme coverage and redox wiring that is governed by the meso-organization and the hydrophobic characteristics of the multilayer assembly.
    Physical Chemistry Chemical Physics 08/2014; 16(38). DOI:10.1039/C4CP02334J · 4.20 Impact Factor
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    ABSTRACT: In this work, the microenvironment of the core of different unimicelles of hyperbranched polyethyleneimine (HPEI) capped with different aliphatic chains (stearate, palmitate, and laurate) dissolved in toluene has been investigated. To achieve this goal we have used 1-methyl-8-oxyquinolinium betaine (QB) as a molecular probe due to its solvatochromic behavior to monitor the micropolarity and hydrogen bond donor ability of the unimicelle cores. QB shows that the micropolarity and the hydrogen bond donor capability of the polar core of reverse unimicellar media are very different than toluene and similar to the one obtained with traditional surfactants that form reverse micellar media but at a very low unimicelle concentration. Particularly, our results show that the hydrogen bonding ability of the core is the driving force for QB to partition toward the unimicellar media.
    Physical Chemistry Chemical Physics 06/2014; 16(26). DOI:10.1039/c4cp01333f · 4.20 Impact Factor
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    ABSTRACT: Hybrid polyelectrolyte multilayer systems were fabricated on top of planar surfaces and colloidal particles via layer by layer (LbL) assembly of polystyrene sulphonate (PSS) and polybenzyl methacrylate-block-poly(dimethylamino)ethyl methacrylate (PBzMA-b-PDMAEMA) polymersomes. Polymersomes were prepared by self assembly of PBzMA-b-PDMAEMA copolymer, synthesised by group transfer polymerisation. Polymersomes display a diameter of 270nm and a shell thickness of 11nm. Assembly on planar surfaces was followed by means of the Quartz Crystal Microbalance with Dissipation (QCM-D) and Atomic Force Microscopy (AFM). Detailed information on the assembly mechanism and surface topology of the polymersome/polyelectrolyte films was thereby obtained. The assembly of polymersomes and PSS on top of silica particles of 500nm in diameter was confirmed by ζ-potential measurements. Confocal laser scanning microscopy (CLSM), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) revealed that polymersome/PSS coated silica particles increase in total diameter up to 3-5μm. This hints toward the formation of densely packed polymersome layers. In addition, CLSM showed that polymersome/PSS films exhibit a high loading capacity that could potentially be used for encapsulation and delivery of diverse chemical species. These results provide an insight into the formation of multilayered films with compartmentalised hydrophilic/hydrophobic domains and may lead to the successful application of polymersomes in surface-engineered colloidal systems.
    Journal of Colloid and Interface Science 05/2014; 421:132–140. DOI:10.1016/j.jcis.2014.01.038 · 3.55 Impact Factor
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    ABSTRACT: The mesostructural and electrochemical characterization of a redox-active polyelectrolyte-surfactant complex formed by polyallylamine tagged with an osmium complex and dodecylsulfate is presented. X-ray reflectivity (XRR), grazing-incidence small-angle X-ray scattering (GISAXS), X-ray photoelectron spectroscopy (XPS), contact angle goniometry (CA) and cyclic voltammetry (CV), including the numerical simulation of the voltammetric response, were employed to analyze the structure, stability and the electrochemical response of these supramolecular films. In contrast to redox-active polyelectrolyte multilayers (PEMs), the self-assembled system presented here shows a mesoscopic order yielding a film of layered structure very stable to an aqueous environment where the hydrophilic moieties (amino and sulfate groups) are not exposed to the solution since a contact angle of 95° is observed upon exposure to water. However, the film shows a self-exchange electron transfer mechanism with an apparent diffusion coefficient of 2 × 10−9 cm2 s−1 for a film of 300 nm of thickness. This behavior shows that the film exposed to an aqueous solution undergoes a fast electron transfer process to/from the electrode surface and ions to/from the electrolyte solution.
    Electrochimica Acta 02/2014; 118:124–129. DOI:10.1016/j.electacta.2013.11.188 · 4.09 Impact Factor
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    ABSTRACT: Abstract The supramacromolecular structure of core-shell amphiphilic macromolecules (CAMs) with Hyperbranched Polyethyleneimine (HPEI) cores and fatty acid chain shells (HPEI-Cn) for different chain lengths was investigated both, in colloidal suspension, solid phase and at the air-water interface using Small Angle X-ray Scattering (SAXS), Wide Angle X-ray Scattering (WAXS), X-ray Reflectometry (XRR) and Langmuir isotherms. At low temperatures colloidal toluene suspensions of the HPEI-Cn polymers form, as evidenced by peaks arising in the structure factor of the system showing mean particle-to-particle distances correlated to the length of the aliphatic chains forming the shells of HPEI-Cn unimicells. The CAM sizes as found from the SAXS experiments also display a clear dependence on shell thickness suggesting that the aliphatic chains adopt a brush-like configuration. After solvent extraction, HPEI-Cn adopts ordered structures with hexagonal packing of the aliphatic chains. Submitted to lateral pressure Π at the air-water interface, HPEI-Cn undergoes a disorder-order transition with increasing transition pressure for increasing chain lengths. The CAMs show different behavior in-plane and out-of-plane. While out-of-plane the aliphatic chains behave as a brush remaining almost fully unfolded, whereas parallel to the air-water interface the chains fold down in a mushroom way with increasing lateral pressure Π.
    Journal of Colloid and Interface Science 01/2014; DOI: · 3.55 Impact Factor
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    ABSTRACT: Combined use of electrochemical techniques (electrochemical impedance spectroscopy and cyclic voltammetry) and quartz crystal microbalance with dissipation allowed to resolve separately the thermal effects on diffusion and electron-transfer steps of the electrochemical reaction of the [Fe(CN)6]3–/4– redox couple at a Au electrode modified with poly[2-(methacryloyloxy)ethyl]trimethylammonium chloride (PMETAC) brushes. Arrhenius-type dependences of the kinetic constant and the diffusion coefficient with temperature were observed in different electrolytes. Ion-paired collapsed polyelectrolyte brushes in NaClO4 result in compact stiff structures with less amount of entrapped water and markedly different from the same brushes with a collapse driven by pure Coulombic screening in NaCl. A remarkable difference related to the type of counterion is the occurrence of a thermal transition for the polyelectrolyte brush in the presence of ClO4– ions at near-ambient temperature (17 °C). Activation energies for electron-transfer and diffusion processes become twice as large as those for temperatures above the thermal transition. These electrochemical studies demonstrate not only the critical role of ion-pairing interactions in determining the physicochemical properties of the macromolecular system but also provide experimental evidence of counterion-induced thermocontrolled transport functionality in the polyelectrolyte brush layer.
    The Journal of Physical Chemistry C 12/2013; 117(50):26680–26688. DOI:10.1021/jp410123d · 4.84 Impact Factor
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    ABSTRACT: We present a method to include Pt nanoparticles of 3nm average diameter with potentially tunable catalytic activity within mesoporous silica thin films of 9 nm pore diameter. This method is based in the control of the mesopore surface charge by the controlled growth of a short brush copolymer. The resulting metal-polymer-mesopore nanocomposite is accessible and presents high catalytic activity towards ammonia oxidation even at low temperatures with 2% weight Pt loading. An anomalous partial selectivity towards nitrous oxide is observed for the first time, which can be due to the synergy of the particles and the modified surface. This effect opens a path towards the design of nanocomposite catalysts with highly controlled environments, in which the synergy of size- and function-controlled cavities can be tuned in order to lower the reaction barriers. We propose that the observed selectivity shift towards nitrous oxide production can be closely related to an increment of the oxygen supply to the reaction system generated by the polymer support of the Pt nanoparticles.
    ACS Applied Materials & Interfaces 09/2013; 5(18). DOI:10.1021/am403836f · 5.90 Impact Factor
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    ABSTRACT: Devising strategies to assess the glass transition temperature (Tg) of polyelectrolyte assemblies at solid-electrolyte interfaces is very important to understand and rationalize the temperature-dependent behavior of polyelectrolyte films in a wide range of settings. Despite the evolving perception of the importance of measuring Tg under aqueous conditions in thin film configurations, its straightforward measurement poses a challenging situation that still remains elusive in polymer and materials science. Here, we describe a new method based on electrochemical impedance spectroscopy (EIS) to estimate the glass transition temperature of planar polyelectrolyte brushes at solid-liquid interfaces. To measure Tg, the charge transfer resistance (Rct) of a redox probe diffusing through the polyelectrolyte brush was measured, and the temperature corresponding to the discontinuous change in Rct was identified as Tg. Furthermore, we demonstrate that impedance measurements not only facilitate the estimation of Tg but also enable a reliable evaluation of the transport properties of the polymeric interface, i.e., determination of diffusion coefficients, close to the thermal transition. We consider that this approach bridges the gap between electrochemistry and the traditional tools used in polymer science and offers new opportunities to characterize the thermal behavior of complex polymeric interfaces and macromolecular assemblies.
    Analytical Chemistry 06/2013; 85(14). DOI:10.1021/ac4007655 · 5.83 Impact Factor
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    ABSTRACT: The supramolecular structural aspects of hetero-assemblies constituted of gold nanoparticles capped with amphiphilic unimolecular micelles were studied using synchrotron-based small angle X-ray scattering (SAXS). Experimental results revealed that straightforward transfer of citrate-capped Au nanoparticles from an aqueous environment to a toluenic solution of amphiphilic hyperbranched polymers results in the spontaneous integration of the nanocrystals into the extended hydrophilic domains of self-assembled supramolecular structures. In this way, we were able to self-organize metal-polymer nanoarchitectures in solution displaying interesting thermoactive functions, i.e.: hybrid assemblies exhibiting negative thermal expansion coefficients. We consider that this strategy has potentiality to realize self-organized supramolecular hetero-assemblies as it provides an alternative methodology to spontaneously integrate nanoscale building blocks into preformed supramolecular objects.
    Journal of Colloid and Interface Science 01/2013; 397. DOI:10.1016/j.jcis.2013.01.004 · 3.55 Impact Factor
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    ABSTRACT: This work describes the synergistic combination of ionic self-assembly and recognition-directed assembly with the aim of creating highly functional bioelectrochemical interfaces compatible with the supramolecular design of a wide variety of biosensing platforms. A recently synthesized glycopolyelectrolyte constituted of polyallylamine bearing redox-active osmium complexes and glycosidic residues (lactose) is used to create a self-assembled structure with sodium dodecylsulfate. In turns, this supramolecular thin films bearing redox-active and biorecognizable carbohydrate units enable the facile assembly of functional lectins as well as the subsequent docking and "wiring" of glycoenzymes, like horseradish peroxidase (HRP) (an elusive enzyme to immobilize via noncovalent interactions). The assembly of this system was followed by quartz crystal microbalance and grazing-incidence small-angle X-ray scattering (GISAXS) studies confirmed that spin-coated ionically self-assembled films exhibit mesostructured architectures according to the formation of self-organized lamellar structures. In-depth characterization of the electrocatalytic properties of the bio-supramacromolecular assemblies confirmed the ability of this kind of interfacial architecture to efficiently mediate electron transfer processes between the glycoenzyme and the electrode surface. For instance, our experimental electrochemical evidence clearly shows that tailor-made interfacial configurations of the ionic self-assemblies can prevent the inhibition of the glycoenzyme (typically observed in HRP) leading to bioelectrocatalytic currents up to 0.1 mA cm-2. The presence of carbohydrate moieties in the ionic domains promotes the biorecognition-driven assembly of lectins adding a new dimension to the capabilities of ionic self-assembly.
    Analytical Chemistry 01/2013; 85(4). DOI:10.1021/ac303424t · 5.83 Impact Factor
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    ABSTRACT: The aggregation behavior and morphological characteristics of amphiphilic block copolymer polybenzyl methacrylate-block-poly(dimethylamino)ethyl methacrylate (PBzMA-b-PDMAEMA) at the air-water interface were investigated through surface pressure measurements, atomic force microscopy (AFM) imaging, electrochemical measurements and X-ray reflectivity. Ionization of PDMAEMA blocks significantly affects the isotherms of the surface films at the air-water interface and, consequently, originates different morphologies of Langmuir-Blodgett films obtained under different experimental conditions. At low pH the PDMAEMA blocks are fully protonated and therefore dissolved in the aqueous subphase. Under this condition, the effects of the solubility and electrostatic repulsion of submerged PDMAEMA chains prevail over hydrophobic interactions and the Langmuir film exhibits low surface pressure at large molecular area values. Upon compression, the isotherm shows a pseudoplateau corresponding to the pancake-to-brush transition followed by an increase in surface pressure at smaller MMA values. These results were correlated with the morphological features of Langmuir–Blodgett films transferred onto silicon substrates, where dispersed dot-like domains that gradually transformed into an island-like structure, followed by further percolation into a continent-like morphology, were observed through AFM imaging. On the other hand, at high pH the isotherm is more expanded and the film exhibits higher surface pressure at relatively high MMA values due to the strong repulsive interactions between interface-confined hydrophobic aggregates constituted of PBzMA cores and neutral PDMAEMA shells. In this case, the AFM results show a structural evolution from circular and quasi-hexagonally packed micelles, followed by a worm-like structure that collapses into a homogeneous film. Furthermore, the study of the copolymer behavior under different subphase ionic strength conditions confirmed the critical role of electrostatic interactions in determining the characteristics of the isotherm. We could also demonstrate that our system follows accurately the scaling relationship for surface pressure of annealed brushes. Complementary studies performed by means of X-ray reflectivity were carried out to probe the buried interfacial structure of the diblock copolymer film, corroborating that the organization of both blocks on the silicon substrates is strongly dependent on the pH conditions of the subphase during the LB transfer.
    Soft Matter 01/2013; 9(45-45):10899-10912. DOI:10.1039/C3SM52336E · 4.15 Impact Factor
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    ABSTRACT: Silicon nanoparticles of 1−5 nm size (SiNPs) were synthesized by a bottom-up (BU) approach involving a chemical wet method. The contribution of different emitters to the overall excitation−emission matrix was analyzed on the assumption that pure substances existing in a unique form show an excitation wavelength-invariant emission spectrum. The occurrence of emitters differing in size and aggregation was supported by transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), time-resolved single photon counting, and time-resolved anisotropy experiments. The effect on photoluminescence (PL) of the particle surface oxidation as a result of aging is studied and compared to that of surface oxidized particles obtained by a top-down (TD) approach following an electrochemical method with HF etching. Surface oxidation to SiO x seems to introduce two different effects on the SiNP PL. An emission originated in surface states associated to SiO x was identified and observed for SiNPs synthesized by both BU and TD approaches. Blue-shifted excitation−emission spectra associated to a silicon core in embedded SiO x nanostructures were also identified. Theoretical studies were carried out to help understand the observed results. S ilicon nanoparticles of 1−5 nm size (SiNPs) received great attention, as they combine size-dependent photolumines-cence (PL) with the richness of silicon surface chemistry. 1 The momentum requirements which make bulk Si a rather inefficient light emitter are relaxed in the 1−5 nm size silicon crystals as a result of quantum confinement effects. 2 The optical emission properties of these chromophores can be tailored by suitably adjusting the height and width of the potential that confines electrons and holes. In spherically shaped colloidal dots, the band gap and oscillator strength can be tuned by variation of the diameter. 3 Silicon in the form of small structures shows a special interest because it is promising for light-emitting optoelectronics, 4 for photonics, 5 for light emitters in biological labeling, 6 and as photosensitizers of singlet oxygen. 7 Silicon nanoparticles can be produced by comparatively simple methods. The synthesis procedures include electro-chemical HF-mediated etching of crystalline Si wafers to yield porous silicon and further dispersion of the particles by ultrasound, 8 gas-phase synthesis, 9,10 and chemical reaction of Si precursors in solution. 11−14 However, significant differences are reported in the room-temperature PL of apparently similar particles obtained by different synthetic routes, as depicted in Table 1. The wave functions of electrons and excitons in silicon nanoparticles of sizes smaller than the Bohr radius in bulk silicon (∼ 4.5 nm) are delocalized over the nanoparticle volume. 2,15 Therefore, the optical properties are sensitive not only to the size of the particles but also to the surface chemistry, network distortion, and geometry of the structures. 15 The difficulty in controlling these parameters during synthesis may introduce variability and contradiction within the results reported by different groups. The important role of surface reconstruction and composition in determining the PL
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    ABSTRACT: This work explores the synergistic combination of ionic self-assembly and recognition-directed assembly for the modification of electrode surfaces with redox glycoenzymes on the basis of electroactive glycopolyelectrolyte-surfactant complexes.
    Chemical Communications 10/2012; 48(88):10868-70. DOI:10.1039/c2cc35949a · 6.72 Impact Factor

Publication Stats

2k Citations
638.84 Total Impact Points


  • 2001–2015
    • National University of La Plata
      • • Instituto de Investigaciones Físicoquímicas Teóricas y Aplicadas (INIFTA)
      • • Facultad de Ciencias Exactas
      Eva Perón, Buenos Aires, Argentina
  • 2005–2011
    • National Scientific and Technical Research Council
      • INIFTA Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas
      Buenos Aires, Buenos Aires F.D., Argentina
  • 2008–2009
    • Max Planck Institute for Polymer Research
      Mayence, Rheinland-Pfalz, Germany
  • 2005–2009
    • University of Cambridge
      • Department of Chemistry
      Cambridge, England, United Kingdom
  • 2007
    • University of Lausanne
      • Department of Fundamental Microbiology (DMF)
      Lausanne, Vaud, Switzerland
  • 2001–2004
    • Universidad de La Laguna
      San Cristóbal de La Laguna, Canary Islands, Spain