RAMAN SPECTROSCOPY

Author: RAMOS PABLO MANUEL.
Year: 2005.
University: ROVIRA I VIRGILI [www.urv.cat].
Place of defense: FACULTAT DE QUIMICA.
Place of preparation: FACULTAT DE QUIMICA. URV..

Author: SINGH GAJENDRA PRATAP.
Year: 2005.
University: POLITÉCNICA DE CATALUÑA [www.upc.edu].
Place of defense: Aula de teleensenyament-CAMPUS NORD.
Place of preparation: C4 Jordi Girona, 1-3, campus nord 08034.

Summary: The biochemical analysis are dependent on work, not apply to single cells and can not monitor changes on the spot. The Raman spectroscopy is an established technique for the identification of chemical molecules. The development of the Raman spectroscopy (and Raman images) for simple living cells is particularly interesting in cellular and molecular biology, because it helps to observe and understand important cellular processes in real time and simple cells. The optical tweezers, which are based on the principle of radiation pressure, using a laser beam is not homogeneous heavily focused to manipulate microparticles. Since the natural environment for many living cells are suspended, you can easily combine the techniques of optical tweezers and Raman spectroscopy (OTRS) to detain this cell type in the solution and study the biochemical changes within the cell real time. Since the year 2002 is used to study the OTRS living cells, although the results described have not proven their usefulness to monitor biochemical changes in real time within living cells floating simple. This thesis has been studied OTRS's ability to conduct such oversight. It has sought a solution to the following problems: 1. OTRS implement a system with the ability to perform Raman spectrum measurements for several hours with minimal intervention in the biochemical processes of a cell optically trapped. 2. Consider how cell growth in an optical trap affects the process of data acquisition Raman. 3. Software to develop a mathematical treatment of data acquired Raman. 4. Perform a set of experiments model that can demonstrate the ability to monitor biochemical processes in a cell optically trapped: a) to study the effects on cell changes in environmental conditions and b) to study the cell cycle. Chapter 1 describes in detail the system and his art. Chapter 2 explains the life processes in yeast cells and theory for them the techniques of optical tweezers and Raman spectroscopy. Chapter 3 focuses on the pilot. When a living cell grows, it changes its shape and size. This, together with the Brownian motion, it can affect their position in the optical trap that can affect the result of Raman spectra acquired and could lead to misinterpretation of results. Chapter 4 discusses the effect of cell growth in the process of the acquisition of the Raman spectra. In the presence of a high concentration of glucose in the surrounding environment triggering a response to stress hiperosmotica. The cell cycle and cell mutates to a form anaerobica and produce ethanol, carbon dioxide and glycerol which helps maintain the osmotic pressure through the cell membrane. We detected the presence of glycerol and ethanol as we detailed in Chapter 5. In chapter 6 biochemical processes of the cell were studied. The temporal behavior of the Raman peaks observed was different during the delay in the final stage of late. The observed changes in the Raman spectra in the last phase G1 or the beginning of S phase corresponded to the growth of an outbreak. As a control, the Raman spectra of the cells no-vivas were also analyzed. The Raman scattering can be improved by the presence of nanostructuras or metal nanoparticles. The increased surface Raman spectroscopy (SERS) can achieve a better ratio of the signal / interference and Chapter 7 we considered how the Raman spectra change in the presence of nanoparticles of silver in the vicinity of a single living cell. In Chapter 8 provides conclusions and a list of publications.

Author: CAÑAMARES ARRIBAS M. DE LA VEGA.
Year: 2005.
University: COMPLUTENSE DE MADRID [www.ucm.es].
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: INSTITUTO DE ESTRUCTURA DE LA MATERIA, CONSEJO SUPERIOR DE INVESTIGACIONES CIENTÍFICAS.

Summary: The identification of pigments used in works of art is crucial in the analysis of the constituent materials and the technical implementation delas same, which can facilitate the choice of the most appropriate method of restoration and conservation of works, as well as solve the potential problems dating and authentication of art objects. In recent years, Raman spectroscopy has been established as the best technique for rapid identification of pigments, primarily inorganic. However, the use of this technique in the study of organic pigments have been much lower, because many of them are fluorescent photosensitive or not give rise to a significant Raman spectrum due to its high or low dilution section effective Raman . This thesis has been carried out successfully the identification and characterization of three vibrational organic pigments of interest in the Artistic Heritage (alizarina, carminic acid and curcumin) through empello of Raman intesificada by surface spectroscopy (Surface Enhanced Raman Spectroscopy, SERS). This technique, based on Raman spectroscopy, used metal surface nanostructures to mitigate the high fluorescence emission of substances with large fluorescent pigments as the object of study, allowing the analysis of their Raman spectra. Another advantage of spectroscopy SERS is its high sensitivity, which enables the detection of pigment to very low concentrations of up to 10 -7ÇM in the case of alizarina. One of the most notorious aspects of this work is the preparation and characterization of comparative media SERS by novel methods (for reducing chemical hydroxylamine hydrochloride, laser ablation and fotorreducción spot), in order to determine the best method for analysis the pigments. In connection with the study of pigments, it has been carried out both in solution using different wavelengths of excitation (514.5 - 785 and 1064 nm) and in various conditions of pH and concentration, as several carriers interest in Artistic Heritage (pigment pressed on paper and on a sample of egg tempera). At the same time, the study of decomposition of curcumin after irradiarla with ultraviolet light and the interaction of alizarina with egg albumin, and it is used as algutinante in tempera paints. The studies and results presented in this thesis has shown that it is possible to successfully implement the SERS spectroscopy to the study of organic pigments of interest in the historic Artistic Heritage, both in solution and in various solid supports.

Author: Campillo Funollet Marc.
Year: 2006.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAT DE CIENCIES.
Place of preparation: Facultat de Ciencies.

Summary: The work outlined in this dissertation have focused on improving the properties of dental materials and the development of techniques to enable its evaluation. The thesis is presented that has been structured in three blocks. In the first, has developed a new material through modification of a dental adhesive with a commercial ion exchange resin loaded with fluoride ion and has been characterized both the fluoride ion release of the new material and its strength accession. Secondly, we have explored new methods of analysis based on the diffraction of X-rays in the Raman spectroscopy with the aim of studying the addition of fluoride to mineral denal. Finally, it has also studied the effect of the addition of Fe (III) to a tooth bleaching based carbamide peroxide with the purpose of studying the possibility of speeding up the process of laundering mediane a reaction type Fenton.