Synthesis of Silica Nanoparticles coated with gold nanoshells (Au/SiO2) using continuous flow microreactors

LAURA GUTIERREZ, LEYRE GÓMEZ, MANUEL ARRUEBO, JESÚS SANTAMARÍA

Córdoba

Taller; "Plasmones 2011” . Taller Satélite XVII Congreso Argentino de Fisicoquímica; 2011

FCEyN – UBA

Mass production is a serious concern in the synthesis of nanostructured materials due to the great demand of those materials and, for that reason, continuous synthesis procedures are sought. When using discontinuous (batch) reactors in the synthesis of nanoparticles several drawbacks usually emerge such as: i) an heterogeneous distribution of reactants and temperatures in the reactor, ii) insufficient mixing, iii) the synthesis yield is usually low, v) among others. In order to overcome these disadvantages microfluidic reactors have been used in the synthesis of nanoparticles to control more precisely reaction temperatures and residence times, rendering, in a continuous way, nanoparticles with narrow particle-size distributions [2]. On the other hand the ability of core/shell Au/SiO2 nanoparticles (NPs) to heat upon being exposed to near-infrared (NIR) radiation is well known. This region of the electromagnetic spectrum is notable for minimal absorption by water and biological chromophores. Therefore, NIR light is preferable as trigger in biomedical applications because it has maximal penetration in tissues due to their minimal absorbance at those wavelengths. By varying the relative sizes of the dielectric core diameter and gold shell thickness the plasmon resonance wavelength can be tuned to any desired wavelength across a large region of the infrared spectrum. To synthesize NPs based on the coating of SiO2 nanoparticles with a thin of Au by using continuous-flow methods to be used in biomedical applications (photothermal therapy).                                                q     To analyze the advantages of using micromixers versus batch reactors in the synthesis of silica nanoparticles coated with gold q     To study the reproducibility of the synthesis methods. q     To investigate the effect of the temperature, residence time and reagent ratios on the particle size distribution and their polydispersity. q     To synthesize Au/SiO2 nanoparticles wich absorbed at near-infrared (NIR) radiation (800 nm)