0000000000061916
AUTHOR
Irene Domínguez
The wet synthesis and quantification of ligand-free sub-nanometric Au clusters in solid matrices.
© The Royal Society of Chemistry. The synthesis of ligand-free sub-nanometric metal clusters on a large scale suffers typically from very low yields (15% yields, as unambiguously determined using a very simple and extremely sensitive analytical reaction test.
Electrochemical tomato (Solanum lycopersicum L.) characterisation using contact probe in situ voltammetr
[EN] An in situ electrochemical contact probe methodology for characterising tomato samples is proposed. It is based on the record of the voltammetric response of antioxidant compounds when glassy carbon electrodes are inserted into the pericarp of fresh tomato specimens cut in half. The absence of pretreatment and in situ sampling avoid sample contamination and the oxidation of air-sensitive compounds thus increasing the representativity of the analytical data relative to conventional electrochemical analysis. Characteristic voltammetric responses recorded for such compounds, including rutin, chlorogenic acid, naringenin, naringenin chalcone and ascorbic acid have been obtained. A positive…
Screening and authentication of tea varieties based on microextraction-assisted voltammetry of microparticles
Abstract A simple electrochemical methodology for screening and authentication of green, black and red tea varieties is proposed. It is based on the record of the voltammetric response of microparticulate films of antioxidant compounds resulting from an ethanolic micro-extraction of commercial tea herbal preparations in contact with aqueous buffers. The obtained voltammetric responses led us to differentiate between diverse tea varieties upon application of bivariant and multivariant chemometric techniques, including discrimination of mixtures of teas with sensitivity estimated of 5.0 μA mg −1 with a detection limit of 0.01 mg of tea sample. Under the proposed conditions 100% discrimination…