24 documents found, page 1 of 3
Near-Infrared Luminescence from Visible-Light-Sensitized Ruthenium(II)-Neodymiu...
Sábio,Rafael M.; Santagneli,Silvia H.; Gressier,Marie; Caiut,José M. A.; Pazin,Wallance M.; Silva,Robson R.; Ribeiro,Sidney J. L.; Menu,Marie-JoëlleNew infrared emitting d-f (ruthenium(II)-neodymium(III)) heterobimetallic complexes with alkoxy(silyl) functional groups have been prepared. Visible excitation evidenced energy transfer processes from the ruthenium(II) donor to neodymium(III) acceptors leading to infrared emission. Energy transfer rates (kEnT) and efficiency of energy transfer (ηEnT) are, respectively, 0.61 × 107s-1 and 44% for RuL1-NdL3 comple...
DETECTION OF THE PEPTIDE P17-1 (HIV) BY SURFACE ENHANCE RAMAN SCATTERING (SERS)
Carneiro,Leandro B.; Moraes,Marli L.; Ribeiro,Sidney J. L.; Brolo,Alexandre G.A bioanalytical method for HIV detection based on surface-enhanced Raman scattering (SERS) is described. The assay targeted the peptide p17-1. This peptide sequence is present in the protein p17, a structural protein essential in the life cycle of the human immunodeficiency retrovirus (HIV). The antibody anti-p17 was immobilized in a planar gold surface using self-assembled techniques. This planar platform was ...
Cr3+ Doped Al2O3 Obtained by Non-Hydrolytic Sol-Gel Methodology
Caiut,José M. A.; Floch,Nolwen; Messaddeq,Younès; Lima,Omar J. de; Rocha,Lucas A.; Ciuffi,Katia J.; Nassar,Eduardo J.; Friedermann,Geraldo R.This paper reports the synthesis and characterization of Cr3+-doped alumina by the sol-gel non-hydrolytic methodology. The resulting sample was treated at different temperatures. X-ray diffraction revealed that the ruby phase emerged in the sample treated at 1100 ºC, which was later confirmed by absorption bands correspondent to Cr3+ ions allowed transitions at 4A2 → 4T1, 4T2, and forbidden at 4A2 → 2T1, 2E, ob...
Electrical Immunosensor Made with Antigenic Peptide NS5A-1 Immobilized onto Sil...
Lima,Lais R.; Gonçalves,Alem-Mar B.; Paulovich,Fernando V.; Oliveira Jr.,Osvaldo N.; Ribeiro,Sidney J. L.; Moraes,Marli L.Immunosensors based on impedance spectroscopy for diagnosing hepatitis C are reported where the sensing units were made with the antigenic peptide PPLLESWKDPDYVPPWHG (NS5A-1) derived from the NS5A protein of the hepatitis C virus (HCV) immobilized in layer-by-layer (LbL) films with silk fibroin (SF) and deposited on gold interdigitated electrodes. The electrical response of the sensing units varied upon immersi...
Facile Synthesis of Tellurium Nanowires and Study of Their Third-Order Nonlinea...
Silva,Robson R.; Mejia,Hans A. G.; Ribeiro,Sidney J. L.; Shrestha,Lok K.; Ariga,Katsuhiko; Oliveira Jr.,Osvaldo N.; Camargo,Vanessa R.; Maia,Lauro J. Q.We report on the synthesis of single-crystalline tellurium nanowires with different aspect-ratios prepared via facile surfactant-assisted synthesis under mild conditions. Short and long Te nanowires were synthesized by the reduction of tellurium dioxide by hypophosphorous acid with the assistance of polyoxyethylene (23) laurylether and cetyltrimethylammonium bromide, respectively. We obtained uniform single-cry...
MATERIAIS VÍTREOS E LUZ: PARTE 1
Nalin,Marcelo; Ribeiro,Sidney J. L.; Manzani,Danilo; Gonçalves,Rogéria Rocha; Poirier,Gael; Cassanges,Fabia Castro; Matos,Christiano J. S. de2015 is the Year of Light, according to UNESCO. Chemistry has a close relationship with light and one of the materials that allows such synergy is glass. Depending on the chemical composition of the glass, it is possible to achieve technological applications for the whole range of wavelengths extending from the region of the microwave to gamma rays. This diversity of applications opens a large range of research...
MATERIAIS VÍTREOS E LUZ: PARTE 2
Nalin,Marcelo; Ribeiro,Sidney J. L.; Manzani,Danilo; Gonçalves,Rogéria Rocha; Poirier,Gael; Cassanges,Fabia Castro; Matos,Christiano J. S. deIn this second part it will be discussed some photonic applications of glassy and glass ceramic thin films which can be used as planar waveguides. Some photonic applications require certain specifications of glass, which can be quantified by studying the nonlinear optical properties of the materials. Therefore, a brief introduction of these phenomena is discussed, as well as the use of femtosecond lasers to man...
Bacterial Cellulose Membranes as a Potential Drug Delivery System for Photodyna...
Peres,Maristela F. S.; Nigoghossian,Karina; Primo,Fernando L.; Saska,Sybele; Capote,Ticiana S. O.; Caminaga,Raquel M. S.; Messaddeq,YounesThe development of drug delivery systems for photodynamic therapy (PDT) is increasingly demanded due to the hydrophobicity presented by most of photosensitizers molecules. Bacterial cellulose (BC), a highly pure cellulose produced by bacteria, possesses the essential features for applications in drug delivery systems, such as large surface area and excellent loading capacity. BC membranes prepared containing a ...
NANOCRISTAIS DE CELULOSE A PARTIR DE CELULOSE BACTERIANA
Lima,Lais R.; Santos,Daniele B.; Santos,Molíria V.; Barud,Hernane S.; Henrique,Mariana A.; Pasquini,Daniel; Pecoraro,Edison; Ribeiro,Sidney J. L.Bacterial cellulose produced from Gluconacetobacter xilinus was used to produce cellulose nanocrystals by sulfuric acid hydrolysis. Hydrolysis was performed with 64% sulfuric acid at 50 ºC with the hydrolysis time ranging between 5 and 90 min. The production of nanocrystals was observed to have size distributions that were dependent on hydrolysis times up to 10 min, after which time the suspensions showed distr...
New Flexible and Transparent Solution-Based Germanium-Sulfide Polymeric Materials
De Salvi,Denise T. B.; Job,Aldo E.; Ribeiro,Sidney J. L.New flexible and transparent materials based on germanium sulfide were obtained using GeCl4 and 1,3-propanedithiol as precursors. These materials have transparency in the ultraviolet-visible (UV-Vis) spectral region (about 70%), thermal stability up to 200 °C and glass transition located at temperatures below 0 °C (-37 °C, -56 °C and -59 °C) as shown by differential scanning calorimetry (DSC) curves. Scanning e...