Dynamic Luminescent Biosensors Based on Peptides for Oxygen Determination

This chapter summarizes the fundamentals of biosensing techniques based on fluorescence spectroscopy and the protagonism of state-of-the-art luminescent biosensors in a wide range of scientific areas, from environmental monitoring to diagnostics and decease treatment, focusing on the paramount contribution of biosensors based on the Förster Resonance Energy Transfer (FRET) transducing mechanism. State-of-the-art FRET biosensors are specially characterized by outstanding sensitivity toward a number of environmental pollutants and dissolved oxygen in aquatic ecosystems, capable of detecting concentrations in the nano and picomolar scales. These biosensors have also been showing impressive performance over other methods in the study of real-time biological processes in vivo relevant to help understanding decease progression like cancer

Electrochemical Biosensors Containing Pure Enzymes or Crude Extracts as Enzyme Sources for Pesticides and Phenolic Compounds with Pharmacological Property Detection and Quantification

Biosensors are chemical sensors in which the recognition system is based on a biochemical mechanism. They perform the specific component detection in a sample through an appropriate analytical signal. Enzyme-based biosensors are the most prominent biosensors because of their high specificity and selectivity; besides being an alternative to the common immunosensors, they are more expensive and present a limited binding capacity with the antigen depending on assay conditions. This chapter approaches the use of enzymes modified electrodes in amperometric biosensing application to detect and quantify pesticides and phenolic compounds with pharmacological properties, as they have been a promising analytical tool in environmental monitoring. These biosensors may be prepared from pure enzymes or their crude extracts. Pure enzyme-based biosensors present advantages as higher substrate specificity and selectivity when compared to crude extract enzymatic biosensors; nevertheless, the enzyme high costs are their drawbacks. Enzymatic crude extract biosensors show lower specificity due to the fact that they may contain more than one type of enzyme, but they may be obtained from low-cost fabrication methods. In addition, they can contain enzyme cofactors besides using the enzyme in its natural conformation

Supramolecular Materials for Optical and Electrochemical Biosensors

It is incontestable that the interactions and bonds that keep molecules united to generate unique supramolecular compounds, with individual properties, morphologies and behaviour, are of special dynamics and singular forces. Therefore, it is necessary to discuss and consider the types of interactions that may occur in a determined system, their dynamics and number, which directly act on the energetic balance that strengthen the union between participants and give rise to a supramolecule

New Materials to Solve Energy Issues through Photochemical and Photophysical Processes: The Kinetics Involved

Kinetic rates of energy production are extremely controlled by the competing processes that occur in systems capable of energy transfer. Besides organic and inorganic compounds already known as electronically actives, supramolecular systems can be thought to form energy transfer complexes to efficiently convert, for instance, light into electricity and the mechanisms for that can be of any kind. Photophysical and photochemical processes can simultaneously occur in such systems to provide energy conversion, by competing mechanisms or collaborative ones. Thus, to investigate the kinetic rates of each process and to understand the dynamics of the electronic excited states population and depopulation in strategically structured materials, can offer important tools to efficiently make use of this not always so evident power of supramolecular materials. In this chapter, we present the state-of-the-art of the use of photophysical processes and photochemical changes, presented by new materials and devices to provide a control of energy transfer processes and enable distinct applications, since energy conversion to sensing and imaging techniques to material characterization

Production of Hydrogen and their Use in Proton Exchange Membrane Fuel Cells

This work will show an overview of the hydrogen production from ethanol by steam reforming method, using distinct catalysts, resulting in low carbon monoxide content in H2 produced; a thermodynamic analysis of reforming employing entropy maximization, the ideal condition for ethanol, and other steam reforming reactions, the state of the art of steam reforming catalysts for H2 production with low CO content. Moreover, in the second part, there will be an overview of the use of hydrogen in a proton exchange membrane fuel cell (PEMFC), the fuel cell operational conditions, a thermodynamic analysis of PEMFC, the catalysts used in the electrodes of the fuel cell, consequences of the CO presence in the hydrogen fuel feed in PEMFC, and the operation conditions for maximum output power density

Fotofisica de hidrocarbonetos aromaticos condensados em matrizes polimericas vinilicas : mecanismo de alargamento espectral

Orientador: Teresa Dib Zambon AtvarsDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de QuimicaMestrad

Photophysical properties of polymers modified with light-emitting groups : crosslinked polyethylenes and poly (methyl methacrylate)

Orientador: Teresa Dib Zambon AtvarsTese (doutorado) - Universidade Estadual de Campinas, Instituto de QuimicaDoutoradoFísico-QuímicaDoutor em Ciência