Brasil State of São Paulo Localization Santo André
The Group www.crespilho.com Frank N. Crespilho Pablo R. S. Abdias Group Leader Synthesis of nanostructured materials using polyelectrolytes Andressa R. Pereira Project: Enzymatic reaction at nanoscale level Aldo Meira Project: Nanoparticles Immobilization on living cells Rodrigo Iost Project: Electrochemical biodevices
The Group The Group w w w. c r e s p i l h o. c o m Dr. Frank N. Crespilho was born November 9, 1978 in Jaú, SP, Brazil. He received a Chemistry Master degree from São Paulo University (Brazil) in 2004 and a Ph.D. from the Chemistry Institute of São Carlos, Brazil in 2007, and went on to study for a Ph.D. (2005-2006) at Coimbra University, Portugal. He occupied the researcher position at the Physics Institute of São Carlos, Brazil until 2008 (Postdoc FAPESP Fellowship). He is now Professor at Federal of ABC University and is also the author of over twenty five published papers and articles. Research interests in the Crespilho group are in the areas of special materials and electrochemistry with emphasis on nanomaterials and the bio-nano interface and devices.
Recent Research Electrochemical Cell at the Nanoscale Level Recently, we have developed and applied nanomanipulation strategies to the build-up of nanoscalecontrolled electrochemical systems. We use distinct lithography procedures to be applied for nanoelectrodes manipulation in the build-up of an electrochemical cell with nanometric dimensions. We have demonstrate the possibility of immobilizing an indium tin oxide (ITO) nanowire electrode on gold contacts deposited atop of a microchip (oxidized Si wafer). A polymer protect layer containing an aperture over the sample area was photolithographically deposited over the microchip to isolate the metallic contacts. We have applied this cell in electrochemical experiments with current rage lower than 100 pa.
Recent Research Biological Molecules and Nanostructures We have exploited the molecular engineering capability of aminoacids to produce a biological hybrid composite, and investigate in detail the mechanisms of formation of the nanostructures, including theoretical modeling. We focus on understanding the mechanisms involved in the formation of the hybrid nanostructures, which is not straightforward, since interactions may occur via non-specific, electrostatic interactions, specific H-bonding and even molecular recognition abilities. The molecular interaction between biological and nanoparticles (Au, Pt, Fe, oxides, etc.) has been investigated using FTIR, UV- Vis and electrochemical datas combined with a DFT theoretical modeling. The origin of the molecular interaction between amino acids and gold nanoparticles: A theoretical and experimental investigation. Chemical Physics Letters, 2009.
Recent Research Molecular Architecture and Charge-Transfer Reactions of Metallophthalocyanine The properties of solid-state supramolecular architectures can be controlled by tuning hydrogen bonding and electrostatic interactions in coordination compounds containing metallic centers and distinct coordination spheres. An interesting strategy to self-assemble highly organized nanostructures is the use of coordination chemistry strategies, where the molecules employed play a key role in the development of supramolecular systems. For example, nickel(ii) and iron(ii) metallic ions, in 3d8 and 3d6 low-spin electronic configurations, respectively, may be present in metallophthalocyanines (MPc, where M is metallic ion), when coordinated to the phthalocyanine ligand (Pc). In water solution, this adduct exhibits high kinetic and thermal stability regarding substitution in the equatorial plane, in addition to being an effective probe for molecular recognition. With the central metal ion being the reactive and catalytic site, metallophthalocyanines may be used as sensor for toxic gases, electrocatalysis, and electrochemical sensors. Moreover, metallophthalocyanines are interesting for electrochemistry studies, in addition to nonlinear optics, optical memories, organic solar cells, and secondary batteries. The electrochemical properties of MPc multilayers films has been studied by our group in collaboration with professor Welter C. Silva group, from UFPI, Piauí-Brazil. Synergistic interaction between gold nanoparticles and nickel phthalocyanine in layer-by-layer (LbL) films: Evidence of constitutional dynamic chemistry (CDC). Phys. Chem. Chem. Phys., 2009.
Recent Research Nanostructured Films Modified Electrodes The use of nanostructured films to modify electrochemical electrodes has allowed a whole host of new systems/devices to be fabricated, with properties that may be tuned upon synergistic interactions between the film components. Films produced with the Layer-by-Layer (LbL) technique, in particular, have opened up the way for new approaches in electrochomism, electrocatalysis, bioelectrochemistry and electroanalysis, for organic and inorganic-organic hybrid nanoarchitectures may be achieved. In addition to the fabrication of novel, optimized materials, with the LbL method fundamental processes such as charge transfer mechanisms involving biomolecules and nanoparticles can be investigated at the molecular level. In this research area, we develop electrochemistry of LbL films, with emphasis on their promising technological applications in electrochemical devices. Development of Highly Selective Enzymatic Devices Based on Deposition of Permselective Membranes on Aligned Nanowires. Journal of Physical Chemistry C, 2009. Enzyme Immobilization on Ag Nanoparticles/Polyaniline Nanocomposites. Biosensor & Bioelectronics, 2009.
Selected Publications The origin of the molecular interaction between amino acids and gold nanoparticles: A theoretical and experimental investigation. Chemical Physics Letters, 2009. Development of Highly Selective Enzymatic Devices Based on Deposition of Permselective Membranes on Aligned Nanowires. Journal of Physical Chemistry C, 2009. Enzyme Immobilization on Ag Nanoparticles/Polyaniline Nanocomposites. Biosensor & Bioelectronics, 2009. Synergistic interaction between gold nanoparticles and nickel phthalocyanine in layer-by-layer (LbL) films: Evidence of constitutional dynamic chemistry (CDC). Phys. Chem. Chem. Phys., 2009.
GMAv Facilities & Technical Skills Layer-by-Layer Self Assemble Technique Bottom-up Nanostructures Synthesis (nanoparticles, nanowires etc.) General Voltammetric Analysis FTIR and UV-VIS Spectroscopy Electrochemical Impedance Spectroscopy (EIS) Scanning Electrochemical Microscopy (SECM) Also, we have a laboratory at UFABC university (Central Multi-usuários) with several equipments and facilities: SEM, FEG, AFM, Optical Microscopy, Chromatography, SECM and others. GMAv has a nanomanipulation laboratory under construction.
Opportunity www.crespilho.com