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The surface-enhanced Raman scattering (SERS) effect and sensor and biosensor analyses are widely applied to investigate drug--biomolecule interactions or to detect trace amount of analytes. In this work, surface-enhanced resonance Raman scattering (SERRS) and an electronic tongue system using impedance spectroscopy were brought together, combining sensitivity and structural level information. Taking advantage of the use of layer-by-layer (LbL) films of phospholipids as biological membrane mimetic systems, cardiolipin (CLP) and dipalmitoyl phosphatidyl glycerol (DPPG) were applied as transducers onto Pt interdigitated electrodes forming an array of sensing units. This e-tongue system was able to detect the phenothiazine methylene blue (MB) below nanomolar concentrations. SERRS was applied to investigate the MB molecular arrangement (monomers or aggregates) when in contact with the phospholipids at trace levels of concentration. The key point was the adsorption of Ag nanoparticles (AgNPs) within the phospholipid LbL films. This approach did not compromise the e-tongue performance and allowed the recording of in situ SERRS spectra for the LbL films after immersion into MB aqueous solutions. The detection of MB through SERRS gave similar results to those reported in the literature but now with an unprecedented sensitivity. 10.1021/ac902585a

The 2PA absorption spectrum of a family of perylene tetracarboxylic derivatives (PTCDs) is investigated. These PTCD compounds exhibit extremely large two-photon absorption (2PA) cross-sections in a wide spectral region, which make them strong candidates for photonics applications involving 2PA.

The results of molecular dynamics simulations of melting and freezing of Nickel and Aluminum nanoparticles at three compositions are explained. The details of the computer simulations, the results and the conclusions are discussed.

The layer-by-layer film fabrication of iron tetrasulfonated phthalocyanine and poly(allylamine hydrochloride) is reported. Spectroscopic and electrochemical data is used for this purpose.