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16 ECSBM, Bochum, Germany, 06.-10.September.2015

6 pags., 5 figs., Piroxicam is a non-steroidal anti-inflammatory drug actually used with limitations because of serious side effects. It is poorly soluble in pure water and exhibit a minimum of four conformers according to the pH conditions of the solution, but not all of them are medically active. In this study, we present, firstly, the Raman characterization of piroxicam in different organic solvents (dimethyl sulfoxide, 1,4-dioxane, ethanol, 1-propanol). These results have permitted us to analyze surface-enhance Raman scattering spectra of piroxicam adsorbed on gold or silver nanoparticles surface at several pHs (1, 2, 4, and 7), imitating the environment of the drug in the body, either in the gastrointestinal tract or in healthy and disease tissues. Results indicate that, below pH = 7, piroxicam is mainly in the zwitterionic conformer, and molecules are oriented parallel to the noble metal surface; however at pH ≥ 7, the main specie detected is the anionic one, differently oriented with respect to the nanoparticle surface. The metal-piroxicam systems here characterized by surface-enhance Raman scattering spectroscopy could constitute nanocarriers in future projects of transporting and releasing of the drug in the body. Copyright © 2015 John Wiley & Sons, Ltd, This work was supported by the Spanish Ministerio de Economía y Competitividad (grant FIS2014-52212-R).

Madrid, Spain, 15–18 June 2014., A wide variety of modern drug delivery systems developed nowadays are is based on nanotechnology. The success of these designs implies minimum of drug loss in the way to disease cells, good recognition of such cells and maximum efficacy in therapeutic effects. In most cases they consist of biocompatible and biodegradable nanostructured materials, like mesoporous silica, capable of include drugs and recognition molecules. One problem associated derives from the use of external molecules acting as linkers when molecules cannot be immobilized in the interior of nanostructures. PBS (polybutylene succinate) is an aliphatic polyester characterized by good mechanical properties and thermal stability but, more importantly, it is biodegradable and biocompatible. Silver nanoparticles present two principal advantages, firstly they act as linkers for the drug to be immobilized in the interior of the nanostructured polymer and secondly they permit and enhancement of the spectroscopic signal by the localized surface plasmon resonances (LSPR) such nanoparticles support.

Escuela Técnica Superior de Ingenieros Industriales (ETSII - UPM), Madrid (Spain), March 11-14 (2014)

J2IFAM 2013 Madrid, February, 13rd-15th 2013

Conferencia, Spanish MINECO (Project FIS2010-15405), Comunidad de Madrid (Project MICROSERES II-S2009TIC-1476) and Grupo Investigacion 950247 of the UCM are gratefully acknowledged for financial support.

Contribution presented at XVIII Congreso Argentino de Fisicoquímica y Química Inorgánica,held in Rosario, Argentina de 9 al 12 de abril de 2013. More details at http://aaifq.org.ar/libroCafqi2013/index.php?controller=render&action=home.

The combined application of SERS (Surface-Enhanced Raman Scattering) and SEF (Surface Enhanced Fluorescence) to the molecular characterization of druǵs nanocarriers based on silver colloids is here shown for the antitumoral drug emodin, and the Non-Steroidal Anti-Inflammatory Drugs indomethacin and ketorolac. The system >silver nanoparticles-emodin> was subsequently embedded in porous silicon and the new system also characterized. The joint analysis of the SERS, SEF and UV-Vis spectra of indomethacin and ketorolac at different pHs has also allowed to propose schemes for the approaching mechanisms of the drug molecules to the silver nanoparticles surface in the pH range studied.© Sociedad Española de Óptica., Se agradece al MINECO (proyecto FIS2010-15405), a la Comunidad de Madrid (proyecto MICROSERES II-S 2009TIC-1476) y al Grupo Investigación 950247 de la UCM, la financiación recibida para llevar a cabo este trabajo.