Thermoplasmonic ssDNA Dynamic Release from Gold Nanoparticles Examined with Advanced Fluorescence Microscopy

Plasmon excitation of spherical gold nanoparticles carrying a fluorescent labeled 30 bp dsDNA cargo, with one chain covalently attached through two S–Au bonds to the surface, results in release of the complementary strand as ssDNA that can be examined in situ using high-resolution fluorescence microscopy. The release is dependent on the total energy delivered, but not the rate of delivery, an important property for plasmonic applications in medicine, sensors, and plasmon-induced PCR

Temperature Dependence of Solar Light Assisted CO2 Reduction on Ni Based Photocatalyst

Methanation of CO2 by H-2 can be in the future an important reaction to store the surplus of renewable electricity during production peaks. The catalytic thermal CO2 methanation (the Sabatier reaction) can be carried out at temperatures above 250 degrees C using Ni supported on silica-alumina (Ni/SiO2-Al2O3). Recently it has been observed that this exothermic reaction can be promoted by solar light irradiation of Ni/SiO2-Al2O3 at initial near ambient temperatures. In the present work we provide a study of the influence of the initial temperature on the photoassisted Ni/SiO2-Al2O3 methanation of CO2, under conditions in which the dark reaction is not observed. An increase of the photoassisted methanation rate with the initial temperature in the range from ambient to 150 degrees C has been observed. The reaction kinetics for lower initial temperatures exhibited an induction period not observed for reactions performed at higher temperatures. The results are discussed in terms of the operation of plasmon photo activation in which the energy of photons is thermalised in a confined space of the active nanoparticles leading to locally high temperatures and the simultaneous photogeneration of electrons and positive holes.Albero Sancho, J.; García Gómez, H.; Corma Canós, A. (2016). Temperature Dependence of Solar Light Assisted CO2 Reduction on Ni Based Photocatalyst. Topics in Catalysis. 59(8-9):787-791. doi:10.1007/s11244-016-0550-xS787791598-9Hammarstrom L, Hammes-Schiffer S (2009) Artificial photosynthesis and solar fuels. Acc Chem Res 42:1859–1860Schlögl R (2015) The revolution continues: energiewende 2.0. Angew Chem Int Ed 54:4436–4439Herron JA, Kim J, Upadhye AA, Huber GW, Maravelias CT (2015) A general framework for the assessment of solar fuel technologies. Energy Environ Sci 8:126–157Hoekman SK, Broch A, Robbins C, Purcell R (2010) CO2 recycling by reaction with renewably-generated hydrogen. Int J Greenh Gas Control 4:44–50Hoch LB, Wood TE, O’Brien PG, Liao K, Reyes LM, Mims CA, Ozin GA (2014) The rational design of a single-component photocatalyst for gas-phase CO2 reduction using both UV and visible light. Adv Sci 1:1400010–1400013Sastre F, Puga AV, Liu L, Corma A, Garcia H (2014) Complete photocatalytic reduction of CO2 to methane by H2 under solar light irradiation. J Am Chem Soc 136:6798–6801Melsheimer J, Guo W, Ziegler D, Wesemann M, Schlögl R (1991) Methanation of carbon dioxide over Ru/titania at room temperature: explorations for a photoassisted catalytic reaction. Catal Lett 11:157–168O’Brien PG, Sandhel A, Wood TE, Jelle AA, Hoch LB, Perovic DD, Mims CA, Ozin GA (2014) Photomethanation of gaseous CO2 over Ru/silicon nanowire catalysts with visible and near-infrared photons. Adv Sci 1:1400001–1400007Ghuman KK, Wood TE, Hoch LB, Mims CA, Ozin GA, Singh CV (2015) Illuminating CO2 reduction on frustrated Lewis pair surfaces: investigating the role of surface hydroxides and oxygen vacancies on nanocrystalline In2O3−x(OH)y. Phys Chem Chem Phys 17:14623–14635Wei W, Jinlong G (2011) Methanation of carbon dioxide: an overview. Front Chem Sci Eng 5:2–10Scaiano JC, Stamplecoskie K (2013) Can surface plasmon fields provide a new way to photosensitize organic photoreactions? Custom applications. J Phys Chem Lett 4:1177–1187Fasciani C, Alejo CJB, Grenier M, Netto-Ferreira JC, Scaiano JC (2011) High-temperature organic reactions at room temperature using plasmon excitation: decomposition of dicumyl peroxide. Org Lett 13:204–207Leadbeater NE (2010) Microwave heating as a tool for sustainable chemistry. CRC Press, Boca Rato

Biological effects of exposure to magnetic resonance imaging: an overview

The literature on biological effects of magnetic and electromagnetic fields commonly utilized in magnetic resonance imaging systems is surveyed here. After an introduction on the basic principles of magnetic resonance imaging and the electric and magnetic properties of biological tissues, the basic phenomena to understand the bio-effects are described in classical terms. Values of field strengths and frequencies commonly utilized in these diagnostic systems are reported in order to allow the integration of the specific literature on the bio-effects produced by magnetic resonance systems with the vast literature concerning the bio-effects produced by electromagnetic fields. This work gives an overview of the findings about the safety concerns of exposure to static magnetic fields, radio-frequency fields, and time varying magnetic field gradients, focusing primarily on the physics of the interactions between these electromagnetic fields and biological matter. The scientific literature is summarized, integrated, and critically analyzed with the help of authoritative reviews by recognized experts, international safety guidelines are also cited

A review on radiation-induced nucleation and growth of colloidal metallic nanoparticles

This review presents an introduction to the synthesis of metallic nanoparticles by radiation-induced method, especially gamma irradiation. This method offers some benefits over the conventional methods because it provides fully reduced and highly pure nanoparticles free from by-products or chemical reducing agents, and is capable of controlling the particle size and structure. The nucleation and growth mechanism of metallic nanoparticles are also discussed. The competition between nucleation and growth process in the formation of nanoparticles can determine the size of nanoparticles which is influenced by certain parameters such as the choice of solvents and stabilizer, the precursor to stabilizer ratio, pH during synthesis, and absorbed dose