ANALYTICAL CHEMISTRY (2)

Author: RODRÍGUEZ CEA ANDRÉS.
Year: 2005.
University: OVIEDO [www.uniovi.es].
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS.

Summary: Chemical analysis of the concentrations of metals and organic compounds in the aquatic environment is not enough to know the real extent in living things. To solve this problem, ecotoxicology modern goes to a new approach based on the evaluation of the response that an agency offers from exposure to chemical agent in the environment. These responses, defined as biomarkers, are a signal integrated to assess the level of pollution in a specific area and are therefore indicative of the level of toxicological risk. The metalotioneínas and cytochromes P450 are bioindicators of pollution by heavy metals and organic compounds respectively. However, the role that the individual plays in the detoxification each of the protein that forms part of these superfamilias protein is not yet completely settled. The purpose of this Doctoral Thesis is the development of analytical methodologies for assessing the potential of metalotioneínas and cytochromes P-450 fish as bioindicators. These methodologies are based on the use of detection techniques chromatography with mass spectrometry with a source of inductively coupled plasma (ICP-MS). The metal speciation analysis has been carried out in three fish species: Anguilla anguilla, Netuma beard and Geophagus brasiliensis. It was observed that exposure to cadmium causes an increase in certain TM isoforms, which could be used as biomarkers. Conducted for the first time speciation of iron in P450 enzymes rainbow trout (Oncorhrynchus mykiss) through HPLC-ICP-MS. Measuring levels of P450 in fish has also been achieved by more conventional techniques such as testing catalytic (EROD) and inmunoquímicos (ELISA and western blotting). Determining levels of the P450 enzymes of brown trout (Salmo trutta) was performed three techniques are applied in a field study. High levels of P450 were correlated with exposure to PAHs in the aquatic environment.

Author: GALERA GARCÍA RAQUEL.
Year: 2005.
University: MURCIA [www.um.es].
Place of defense: FACULTAD DE QUÍMICA, UNIVERSIDAD DE MURCIA.
Place of preparation: FACULTAD DE QUÍMICA, UNIVERSIDAD DE MURCIA.

Summary: In this thesis provides new analytical methods for the determination of therapeutic substances and metabolites using capillary electrophoresis technique. Furthermore, it demonstrates the applicability of the proposed methods for the control of selected analytes in different types of samples, such as branded pharmaceuticals and biological fluids, thereby rapidly in the analysis and an excellent reproducibility in the results. Have been selected as detection techniques, depending on the characteristics of the analytes, spectrophotometry or by laser induced fluorescence, high sensitivity. Using spectrophotometric detection have been separated and identified with excellent results H2 receptor antagonists of histamine, ranitidine and famotidina. It has also achieved an efficient separation by capillary electrophoresis allopurinol and its metabolite oxipurinol species inhibitors of xanthine oxidase acting effectively in the treatment of gout. In other research thesis of this attention has been paid to identifying drug decomposition products of interest. It has proposed a method of capillary electrophoresis free zone for the separation and identification of antipyretic and analgesic acetaminophen and its degradation product, p-aminofenol, providing a much more reliable and easier to those found in the literature. Another problem has been that we have dealt with the separation and determination of creatinine, one of the markers of clinical more interested primarily in kidney patients, in the presence of other substances that may act as potential interfering such as creatine, uric acid and acid p-aminohipúrico . The chromatography capillary electrocinética micelar has been the most effective way to separate the omeprazole, a potent inhibitor of gastric secretion, its metabolites hidroxiomeprazol and omeprazole sulfone. Finally, we applied the laser-induced fluorescence to the determination of species that were not fluorescent characteristics, but which had previously been subjected to a process of derivatization with a fluorescent marker suitable for possible use laser of 488 nm argon. These species have been captopril, a commonly used antihypertensive and antithyroid 2-tiouracilo and 6-fenil-2-tiouracilo. The methods proposed in this thesis has been applied to the analysis of different real samples containing these species, such as pharmaceutical preparations commercial and biological fluids, blood serum and urine, with excellent results in all cases.

Author: ESCUDER GILABERT LAURA.
Year: 2005.
University: VALENCIA [www.uv.es].
Place of defense: Facultad de Química.
Place of preparation: FACULTAD DE QUÍMICA. UNIVERSITAT DE VALÈNCIA.

Summary: Doctoral Thesis This is part of a line of research developed by our research group over the past few years whose overall objective is the development of systems "in vitro", based on chromatography techniques and electroforéticas micelares, for the evaluation of the biological behavior of xenobiotics . This research was raised as a response to the growing demand from the pharmaceutical and chemical industry to provide systems "in vitro" to serve as an alternative or support animal testing for its implementation in the early stages of development new xenobiotics and submit a capability of high performance, which will reduce time, effort and cost pilot. At present, among the alternatives to the use of testing "in vivo" highlights the employing agencies lower unprotected by legislation and vertebrates in the early stages of their development. Of particular interest are methods in vitro using material from these agencies and predictive mathematical models as quantitative structure relationships (QSAR) and retención-actividad (QRAR) that relates quantitatively the biological activity of the xenobiotics with their physicochemical properties or a parameter chromatographic retention, respectively. The hydrophobicity of xenobiotics is a determinant of their physico-chemical properties of their biological activity. His quantification is of great interest in QSAR studies and has a predictive value in a variety of disciplines such as pharmacology, toxicology and environmental control. The classic method for estimating the hydrophobicity of a compound consists in determining their relationship breakdown (logP) in the biphasic n-octanol/water system, using a liquid-liquid extraction system. This method has a number of disadvantages such as high costs, slow, requires very pure compounds and solvents and has a limited range of application. For these reasons, it is strongly committed to the search for new methodologies for estimating the hydrophobicity of the compounds. In 1977 came the first publications to be used in the retention of a compound in phase liquid chromatography in reverse as a measure of its hydrophobicity, causing the studies were called quantitative relationships estructura-retención (QSRRs). Applying this principle to the prediction of the biological activity of a xenobiótico originated studies denominated QRARs. The liquid chromatography micelar (MLC) is a form of reverse phase liquid chromatography using as mobile phases solutions surfactants above its concentration micelar criticism. Under these conditions, the stationary phase is amended by the adsorption of surfactant monomers and the mobile phase micelles exist in equilibrium with the existing surfactant monomers in solution and the stationary phase. At MLC, the solute is shared not only between the mobile phase and stationary phase, but within the mobile phase between water and micela, and the hydrophobicity of a compound is a determinant of their retention. These special characteristics of MLC make it an attractive technique for the estimation of the hydrophobicity of the molecules and suggests that under the appropriate experimental conditions could emulate biological processes sharing. The main objective which arises in this Doctoral Thesis is evaluating the applicability of the MLC in quantifying the hydrophobic properties of bioactive molecules and their possible application for the drug and ecotoxicological evaluation of xenobiotics. For 8 consecuc 19b0 ion of the same the following studies were conducted: First, it addressed the existing problems on the non-linear nature of the relationship between the retention of the compounds in MLC (expressed as the logarithm of the retention factor, logk) and logP. This study was carried out with different sets of neutral compounds eluted with various stages mobile micelares of anionic surfactants, cationic and neutral. For this purpose, we developed a simplex algorithm that showed its validity to model such a relationship and also, more effective than traditional regression models polinómicos. Moreover, the algorithm developed allowed the estimation of the values of logP of new compounds neutral, obtaining values consistent with those obtained experimentally and better than those calculated using commercial software. He then addressed the existing problems in obtaining relations logk-logP for ionic compounds. To carry out this study various models were tested and found to be valid using data retention several families of compounds fellow ionizables eluted with different phases mobile micelares different pH values. It was noted that the retention of ionic compounds can be described in terms of logP and a new descriptor to that call load molar total, more robust than using the specified classic logD (logarithm of the ratio of distribution n-octanol/water) widely used in the literature. The next step was obtaining models retención-hidrofobicidad general, ie applicable to compounds that exhibit a wide variety of physicochemical properties of hydrophobicity, acid and other electronic properties and estéricas. In order to ensure that the hydrophobicity of the compounds is a key factor in retention were used columns C18 and was selected the surfactant no-iónico Brij35 (Polyoxyethylene (23) lauryl ether). It envaluaron different types of variables using multivariate techniques and noted that to describe the retention of MLC unrelated compounds structurally it is necessary to take into account, besides logP, two new descriptors cargo molar negative and positive. On the other hand, analysis of the variables tested showed that the retention of a compound in MLC in the experimental conditions studied is determined primarily by its hydrophobic properties, electronic and to a lesser extent estéricas. Such properties can determine the biological activity of a xenobiótico, which raised the direct use of the retention (obtained with columns C18 and phases mobile Brij35 prepared under physiological conditions of pH and ionic strength) as a variable in predicting the biological activities of xenobiotics. In this new mode of liquid chromatography micelar call chromatography micelar of bio-reparto (CMB). There are a number of similarities between the biomembranas and the CMB. Thus, the disposition of CMB monomers Brij35 adsorbed on the stationary phase was similar to that of phospholipids in biomembranas. In addition, the balance wool / hydrophobic surfactant plays the head of the polar and aliphatic chains of the phospholipids. Finally, the mobile phase consisted of CMB in aqueous solutions of salt micelles in balance with monomers and surfactant prepared under conditions that reproduce the ionic strength and pH of biological fluids, resembles them, basically composed of water, salts, glucose , amino acids, proteins and lipids, which may form aggregates micelares. These similarities justify their success in the following chapters which are used for retention CMB modeling QRAR for describing and predicting the pharmacological activity of two families Therapeutic (local anesthetics and nonsteroidal anti-inflammatory drugs) and Ecotoxicity a broad range of pollutants. The goodness of the models QRAR obtained shows that the system emulates CMB interactions inter-moleculares responsible for the distribution of xenobiotics in biomembranas. Additionally, CMB has a number of advantages over other alternative methodologies, such as precision, automation, versatility, speed and low cost, which make it a tool "in vitro" high yield, attractive and useful for its implementation in laboratories R & D industries. Furthermore, the CMB meets the requirements of European directives which indicate the need for reducing the number of animals used for experimental purposes and replacement of animal testing whenever there another scientific method satisfactory and feasible to obtain the desired result. Finally, we evaluated the potential of chromatography electrocinética using solutions micelares of Brij35 to conduct such studies, specifically applied to the study of ecotoxicity of herbicides fenoxiácidos and compared with the results obtained with CMB, winning both excellent correlations. These results show that the factor obtained in affinity chromatography electrocinética micelar (MEKC) with solutions micelares of Brij35 is also promising a descriptor for the estimation of biological responses to xenobiotics ionized. Additionally, the capillary electrophoresis also meets a number of conditions (high performance in processing samples, low consumption of reagents and samples, versatility and automation) requested at present, the R & D laboratories of industries under the development methodologies in vitro alternatives to the traditional ones.

Author: MOLERO MONFORT MÓNICA.
Year: 2005.
University: VALENCIA [www.uv.es].
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: FACULTAD DE FARMACIA.

Summary: Today, with the development of combinatorial chemistry, summarizes hundreds and hundreds of drugs that show potential biological activity. Studies on drugs, since its discovery until they leave the market, are very costly and time-consuming, involving the selection of candidates and the study of its pharmacokinetic and pharmacodynamic properties. In the early stages of the discovery of a new drug, the pharmacokinetic and pharmacodynamic studies were conducted traditionally on living organisms such as mice, rabbits, dogs, etc.. The studies on the development of new molecules drug candidates require further in its initial stages studies predicting the potential for absorption and permeability of the tested substances. So far in our country these studies are carried out using different techniques "on the spot" or "in vitro" that use of experimental animals. Currently, for ethical reasons and / or economic, are devoting much effort to develop in vitro systems to avoid or reduce the use of these experimental animals. The pharmacodynamic processes and processes based on passive diffusion of drugs has much in common with the fundamental processes of chromatographic separations: they are dynamic processes, the same physicochemical properties of the compounds that determine its activity and its permeability in a biological system are they can determine their retention in a chromatographic system, under conditions cromatograficas adequate and save metabolic processes do not involve breaking links Therefore it is logical to think that there should be relations between the chromatographic retention of a compound and its permeability, and thus its biological activity . In recent years have appeared in the literature various studies which are used chromatographic parameters of drugs such as predictive variables in order to build models retención-actividad biological (quantitative retention-activity relationships, QRAR) This method has an advantage over the QSAR models, as being the chromatographic retention of a composite outcome of a set of interactions (hydrophobic, electronic and estéricas), a single parameter (chromatographic retention, expressed as a factor in retention ko its logarithm logk) can be used as a variable predictor of models QRAR while in QSAR approximate number of descriptors is considerably higher. An additional advantage of the methodology QRAR is that based on dynamic systems, it can be controlled strictly experimental conditions leading to an increase in the reproducibility of results compared with the models based on in vitro cell lines. Our research group has shown that the use of solutions micelares of polioxietilen (23) lauryl ether (Brij35) as a mobile phase and a column C18 in appropriate experimental conditions, provides an environment that allows experimentally reproduce the environment that will find the drug to be administered to a living organism. This methodology to which we have called chromatography micelar of bio-reparto (CMB) has proven useful in obtaining good models for describing and predicting the pharmacokinetic and pharmacodynamic behavior of a large number of drugs and the development of good models to describe and predict absorption of drugs across membranes. The success of the CMB in describing the behavior of drugs in living organisms can be attributed to the similarities between the CMB and chromatographic system interfaces membrane biológica-medio aqueous in living organisms.

Author: FERNÁNDEZ GARCIA BEATRIZ.
Year: 2005.
University: OVIEDO [www.uniovi.es].
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: The fundamental objective of this PhD thesis is the development of analytical methodologies for conducting the characterization of non-conductive materials of industrial interest (homogeneous glasses and thin coatings) and liquid samples of biological significance (desoxinucleótidos) using luminescent Download (glow discharge, GD) both in combination with optical emission spectroscopy (OES) as a mass spectrometry (MS). This basic objective is developed in the following specific objectives: 1-Design of an analytical method for the quantitative analysis of non-conductive homogeneous samples (glass) can be downloaded from radio-luminescent emission spectrometry optics. Discharges luminescent have gained great interest in recent years as a source of atomizació / excitation / ionization detection using as much mass spectrometry as optical emission spectrometry, due to its ability to generate atoms directly from the solid samples. Discharges with luminescent detection by optical emission spectrometry are considered today one of the main techniques for the direct analysis of solid samples due to its reliability, speed and sensitivity. Among the various solid samples due to its reliability, speed and sensitivity. Among the different samples can be studied with this technique are homogenous materials (analysis) and material coatings (in-depth profiles). The GDs can be generated direct current (dc) or radio frequency (rf). Although still under development, the use of rf-GDs has increased in recent years, because in this type of discharge is possible to extend the scope of application to the direct analysis of non-conductive materials. The direct analysis of dielectric materials using rf-GD is the great advantage with this technique compared with its counterpart (dc-GD). However, although analysis of conductive materials (both homogeneous and with coatings) is largely developed, no one has proposed quantification methodologies for conducting the analysis of samples is not conductive to rf-GDs. In this sense, the concept of "continuous emission efficiency" has been widely used in the calibrations multimatriz for analyzing materials drivers dc-GDs. However, the use of emission efficiency has not been investigated so far for the quantification of non-conductive materials. Therefore, the first objective of this dissertation is the development of a simple and reliable analytical methodology for the quantitative analysis of samples is not conductive homogeneous. The methodology was developed using the term "continuous emission efficiency" and using the calibration samples not conductive composition varied. This methodology used corrections to the thickness of the different samples (glass homogeneous). 2-Evaluation of an analytical method for the quantitative analysis of in-depth profile of non-conductive samples (glass with thin layers) can be downloaded luminescent radiofrequency -espectrometría emission optics. Currently thin films and coatings drivers on solid materials are used in a large number of industrial applications in various technological fields, from microelectronics and optics up as protective coatings for a wide variety of sample types. The properties of these thin films depend on the chemical composition, structure and thickness of this layer. Thus, for proper optimization of the properties required by 8 these m 1ff8 ateriales, these chemical parameters must be properly characterized using analytical technique with low detection limits, good reproducibility and high lateral resolution and depth. Discharges luminescent coupled to optical emission spectrometry and mass spectrometry have become a very useful analytical tool for determining the composition of in-depth profiles of samples with coatings. The ability to study the variation in the composition of a material according to their distance from the outer layer using the GDs, stems from the ease with which the layers are removed from the surface to be analyzed in a controlled manner by the process started or "sputtering." Using rf-GD this process "sputtering" takes place Ar + ions with low energy (less 50 eV) and high current density (in the order of 100 mA.mmm-2). The low energy Ar + ions can assure you that the process of "sputtering" takes place without altering the layers to analyze, which is a prerequisite for success for analysis desperfiles deep in thin films. The determination of quantitative profile in depth requires a method of quantification transform measures intensity of emission concentration, and the time set for the quantification of homogeneous samples are not applicable to the measurement of in-depth profiles of overlapping layers. For quantification of in-depth profiles using dc-GDs it has been proposed so far various methods of quantification, however, using rf-GDs yet there is no established method for the non-conductive samples because of the difficulty of controlling the conditions of the electric download. Therefore, the second objective of this dissertation is to develop a simple analytical method for the quantitative analysis of samples with non-conductive thin coatings. The methodology was developed using the concept of "continuous emission efficiency" and is used to assess different types of drivers and non-conductive coatings on homogeneous glasses of different thicknesses. 3-Investigation of the addition of molecular gas (hydrogen, nitró denied or oxygen) in a discharge luminescent RF coupled to optical emission spectrometry. Despite the fact that the argon gas is the most used in the luminescent discharge, in recent years it has carried out studies based on the use of alternative gases and has even experimented with different mixtures of gases, in order to investigate basic processes taking place in the plasma (as are the mechanisms of excitation / ionization), or improve the physical and chemical properties of the sources of GD. Most of these studies have been performed with GDs flow continues. For the most current GDs radio, the papers published to date have focused mostly mixtures argon / helium. In this sense, the third objective of this dissertation is to assess the influence of the addition of molecular gas (hydrogen, nitrogen or oxygen) in the analysis of conductive materials and insulation through rf-GD-OES. The study was conducted in two phases. The first investigate the effect exerted adding controlled either hydrogen, nitrogen or oxygen in a discharge based on argon, on the physical and chemical properties of a rf-GD (emission intensities, speeds and efficiencies booted emission). This comparative study of how the effect of these gases on conductive samples of steel and non-conductive glass samples. Secondly, in order to find a methodology with the best possible resolution in depth to enable the analysis of very thin layers, a study of the effect exerted on the analysis of in-depth profiles of thin films adding controlled these molecular gas. This will carry out an evaluation of the potential generated between the electrodes, the shape of the crater obtained samples (critical parameter in this type of analysis) and the influence of gas added in the resolution of in-depth profiles for samples of glass with different coatings. 4-Design of an analytical methodology for the analysis of non-conductive samples through radio-luminescent discharge mass spectrometry. The coupling of the GDs as a source of ionization mass spectrometry for direct elemental analysis of solids offers significant advantages over optical emission spectrometry, which include: ability to identify most of the elements of the periodic table, obtaining information isotope spectrum in a relatively simple and low limits of detection. In this vein, the use of a GD coupled to a mass analyzer of flight time (TOFMS) for the analysis of samples homogeneous and concentration depth profiles of coated materials, is a powerful analytical tool. On the one hand, for the analysis of samples with coatings source of GDS allows direct analysis of solid homogenous booted through the surface of it, and secondly, the analyzer masses of flight time provides the necessary speed to the extent signals that vary with each instant of time as we enter the sound. In particular, the ability to analysis done by GD-TOFMS presented to reflect the full spectrum of masses with the same accuracy, sensitivity and resolution for all relationships mass / cargo, has provided a strong incentive for the use of TOFMS in this type analysis. In our studies, will investigate the download luminescent RF coupled to mass spectrometry of flight time for the characterization of non-conductive materials. 5, - Assessment of discharges for the luminescent analysis of liquid samples: determination of phosphorus and carbon desoxinucleótidos through downloads luminescent hollow cathode-optical emission spectrometry. The luminescent discharge is being widely used as a technique for direct analysis of solid, both of conductive materials such as semiconductors and insulators because of their ability as a source of atomization, excitation and ionization. However, in recent years it has investigated the use of GDs for the analysis of liquid samples. In this regard, there are some work to develop a source of discharge luminescent coupled to the optical emission spectrometry for the detection of specific liquid samples. In this type of analysis requires an interface that allows the introduction of the sample into the plasma on a continuous basis. The interface interface known as "particle beam" (paticle beam, PB) allows eluyentes introduce a system of liquid chromatography in the source of low pressure while keeping up chromatographic characteristics such as the quality of retention and elution. The interface "beam of particles," consisting of a nebulizer termoconcéntrico, a chamber desolvatación and a camera where the vapors are eliminated waste and reduces the pressure, it produces a fine spray dried from the liquid sample. The coupling of the interface with the source of discharge luminescent hollow cathode (HC) has been investigated in recent years for various types of liquid samples (amino acids, selenium compounds, polycyclic aromatic hydrocarbons, etc..). Therefore, the ultimate objective of this dissertation is to assess the potential of technical PB-HC/GD-OES for the analysis of liquid samples of current biological interest. In our case, we will assess the ability of the technique for the analysis of phosphorus and carbon in different desoxinucleótidos (AMP, ADP, dATP, dCTP and dGTP).

Author: SANCHEZ NUÑEZ NOE.
Year: 2005.
University: OVIEDO [www.uniovi.es].
Place of defense: FACULTAD DE QUIMICA.
Place of preparation: FACULTAD DE QUIMICA.

Summary: In order to introduce the advantages of high speed Liquid Chromatography in pharmaceutical laboratories, a team of HPLC was amended standard for the practice of this new modality. Basically, these changes involve the injection system, the volume of the cell and the response time of the detector and the pipes connecting. The adaptation of the team was assessed using the reproducibility of the retention times and areas of the chromatographic peaks, both in regime isocrático as gradient, and its effectiveness measures widen band instruments and the number of theoretical plates for a standard separation columns with short microdiámetro. The results show a satisfactory adaptation, having achieved a reduction widening extra-columna about five times and increased efficiency around 75% for solutes eluted before five minutes. In addition, it introduced a system to bypass valve injection, as a strategy to reduce stress suffered mechanical columns packed with microparticles. Thus, it developed three analytical methods applicable to the control of the production of active principles: sulbactam, rifabutin and sultamicilina. Its use permits: 1) monitoring and optimization of the processes of synthesis; 2) analysis of the final product; 3) the determination of impurity profile. These new methods substantially improves employees currently in the industry, have reduced their time analyzed in a 70%, which increases the productivity and efficiency of the laboratory, while reducing the cost per analysis. Also, the criteria for validation required by the regulatory agencies have been overcome, which allows submission to the High-Speed Liquid Chromatography as an alternative to conventional HPLC technique used in the pharmaceutical industry.

Author: SANCHEZ NUÑEZ NOE.
Year: 2005.
University: OVIEDO [www.uniovi.es].
Place of defense: FACULTAD DE QUIMICA.
Place of preparation: FACULTAD DE QUIMICA.

Summary: In order to introduce the advantages of high speed Liquid Chromatography in pharmaceutical laboratories, a team of HPLC was amended standard for the practice of this new modality. Basically, these changes involve the injection system, the volume of the cell and the response time of the detector and the pipes connecting. The adaptation of the team was assessed using the reproducibility of the retention times and areas of the chromatographic peaks, both in regime isocrático as gradient, and its effectiveness measures widen band instruments and the number of theoretical plates for a standard separation columns with short microdiámetro. The results show a satisfactory adaptation, having achieved a reduction widening extra-columna about five times and increased efficiency around 75% for solutes eluted before five minutes. In addition, it introduced a system to bypass valve injection, as a strategy to reduce stress suffered mechanical columns packed with microparticles. Thus, it developed three analytical methods applicable to the control of the production of active principles: sulbactam, rifabutin and sultamicilina. Its use permits: 1) monitoring and optimization of the processes of synthesis; 2) analysis of the final product; 3) the determination of impurity profile. These new methods substantially improves employees currently in the industry, have reduced their time analyzed in a 70%, which increases the productivity and efficiency of the laboratory, while reducing the cost per analysis. Also, the criteria for validation required by the regulatory agencies have been overcome, which allows submission to the High-Speed Liquid Chromatography as an alternative to conventional HPLC technique used in the pharmaceutical industry.

Author: FERNANDEZ RODRIGUEZ PABLO.
Year: 2005.
University: OVIEDO [www.uniovi.es].
Place of defense: SERVICIOS CIENTIFICO TECNICOS.
Place of preparation: FACULTAD DE QUIMICA.

Summary: The development of new analytical methodologies and their application to the evaluation of chemical agents in the field of industrial hygiene in general and in atmospheres of work in particular, is of paramount importance today. The establishment by governments or international agencies to limit values that protect the health of workers, eliminating the use of some other compounds or production, regulation through regulations and laws of emissions of hazardous substances require the need current develop analytical techniques that allow the identification of chemicals in the work environment. In this Doctoral Thesis has been developing new strategies and methodologies for the analytical control of chemicals in atmospheres of work, using techniques Inorganic Mass Spectrometry (ICP-MS, ETV-ICP-MS), Infrared Spectroscopy (FTIR) and X-Ray Diffraction (XRD). Specifically: 1. They made a point analytical methodologies for the determination of quartz by FTIR and XRD in respirable dust samples, comparing different media sampling (polyvinyl chloride and nitrate cellulose), and studying the interference that can be found in determining free silica crystalline samples of surface mining operations. The methodology was applied to the analysis of samples taken from different farms in Spain with a view to trying to obtain a list of materials whose contents in quartz is less than 5%, since in these cases the current legislation establishes an exposure limit value "respirable dust" from 5 mg/m3 and suffice to determine the concentration, thus avoiding, routine analysis, the determination of crystalline silica. 2. It has developed a method for the determination of trace metal in atmospheric particles (PM10) by ICP-MS. We studied the conditions for removal of the elements using internal standards to eliminate the potential effects of matrix. The method multielemental developed was applied to the assessment of the levels of metals present in a quarry near the city of Oviedo in order to assess its possible impact on the environment. On the other hand, took place the determination of lead isotope relations samples of PM10 taken in that quarry, in order to identify and discriminate the different sources of lead pollution. 3. We have evaluated the analytical performance of a spectrometer sequential type cuadrupolo and a spectrometer time of flight (TOF) to carry out measures multielementales and multiisotópicas well as measures isotopic relations in fast transient signals as those produced by a vaporizer electrotérmico (VTE) . 4. It has developed an analytical method for the determination of trace and ultra metal samples with high amounts of silicon using the coupling of a vaporizer electrotérmico of tungsten filament with an ICP-MS.

Author: MARTINAVARRO DOMINGUEZ ADRIAN.
Year: 2005.
University: JAUME I DE CASTELLON [www.uji.es].
Place of defense: ESC. SUP.DE TECN. Y CIENCIAS EXPERIMENTALES.
Place of preparation: ESC. SUP.DE TECN. Y CIENCIAS EXPERIMENTALES.

Author: GRINDLAY LLEDÓ GUILLERMO.
Year: 2005.
University: ALICANTE [www.ua.es].
Place of defense: FACULTAD DE DERECHO.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: In recent years he has used microwave radiation (MW) successfully in systems introduction of samples in Atomic Spectrometry (eg ICP-AES and ICP-MS) for the generation and desolvatación aerosol. In both cases, radiation enhances the sensitivity and detection limits obtained with a conventional system to introduce samples (ie nebulizer tire concentric coupled to a camera fogging). However, the results obtained with both systems can be improved further, since the cavity and MW generator used are not the most appropriate for this type of applications. On the other hand, given that the operating principle and the implementation of both systems is similar, it may be possible to develop an integrated system of spraying and desolvatación through microwave radiation. This paper has developed an integrated system of spraying and desolvatación using microwave radiation to ICP-AES using a single cavity MW (MWIS). To do so, first, has been redesigned system generation and application of MW (and cavity magnetron). Then there has been evaluating this new design for fogging (MWTN) and desolvatación (MWDS2) on an individual basis. The main variables studied in both systems have been MW power, the nature of the matrix (inorganic and organic) and the flow of liquid sample (Ql). Based on the findings has been the design of the integrated system of spraying and desolvatación. The results obtained with both the MWDS2 with the MWTN show that the cavity (TM010) and the magnetron used allow for greater efficiency and control in the heating, which provides an improvement in the sensitivity and detection limits in ICP-AES ICP-MS and respect of previous designs of these systems and a conventional system. The running condition for MWDS2 are high power MW, as well as concentrations of matrix and Ql low (<400 Â µ LÂ min-1), while quepara the MWTN is convenient to use powers of MW concentrations dematriz and Ql high ( > 1000 Â µ LÂ min-1). The MWDS2 shown effective in reducing the effects of dissolved organic matrix diluted, allowing direct analysis of samples of wine using a calibrated with patterns of water and internal standard. As to MWTN, has studied the mechanism of aerosol generation and has developed a model able to predict in advance the characteristics of primary aerosol generated. To develop the MWIS it has been necessary to reach a compromise on the experimental conditions of work MWDS2 and MWTN. The results show that, despite the limitations of practical found, MWIS improves the sensitivity and detection limits up to 30 times that of a conventional system introduction of samples.

Author: RODRÍGUEZ GARCÍA ISABEL MARÍA.
Year: 2005.
University: SEVILLA [www.us.es].
Place of defense: INSTITUTO DE RECURSOS NATURALES Y AGROBIOLOGÍA.
Place of preparation: FACULTAD DE QUÍMICAS.

Summary: This thesis presents a study of the chemical composition of the fibers of various herbaceous plants used as raw material for the manufacture of pulp quality, as well as the evolution of its major components during the cooking process in order to obtain better use of these industrial fibers. The fibers selected for this study were: flax (Linom Vistatissimum), hemp (Cannabis sativa), Kenaf (Hibiscus Cannabinus), jute (Corchorus Capsularis), Sisas (Agave Sisalana) and Abacá (Musia Textilis). The study focuses on a general characterization of the fiber based on the quantification of the main fractions (Polysaccharides, Lignin, Extraíbles, Hidrosolubles and ash), with particular emphasis on the detailed study of the composition of the extractable lipofílicos and Lignin, fractions have a special relevance in the manufacture of paper pulp. It also study the behavior and structural changes in lipids and lignin after alkaline cooking.

Author: BENÍTEZ SERRA MIRIAM.
Year: 2005.
University: POLITÉCNICA DE VALENCIA [www.upv.es].
Place of defense: UNIVERSIDAD POLITÉCNICA DE VALENCIA.
Place of preparation: UNIVERSIDAD POLITÉCNICA DE VALENCIA.

Summary: This doctoral thesis aims at the development of organosilicon compounds newspapers mesoporosos (PMOs) fotoactividad. These compounds are hybrid materials in which we have an inorganic matrix determined by the porosity and an organic component that is going to provide a specific functionality. The inorganic portion of these compounds consists of silica and provide a rigid structure with channel with a pore size in the range of mesoporos and high surface area. On the other hand, the organic part of the compound is a molecule fotoactiva. This allows to study the impact of inorganic matrix molecule on its potential application in nanotechnology devices fotoactivos or as adsorbents. In particular, increases the accessibility of organic component that is more willing to interact with other compounds. We have grouped these PMOs into three major groups: The first one will PMOs chiral in which they are used by one side as organic molecules units binaftilo chirality and ciclohexanodiamina. The first of these exhibits an exaltation enantioselectiva their fluorescence in the presence of chiral substrates and thereby indicating the existence of a phenomenon of chiral recognition. The second is a PMO containing units derived from ciclohexildiamina which is used as a reaction medium for the photochemical process di -- methane's dibenzobarreleno. Under these conditions there is a degree of induction asymmetric (25%) notable for having achieved by a photochemical transformation and above achieved using similar systems based on zeolites. The second group will PMOs with a possible application in fotoelectrónica capable of generating second harmonic or electroluminescent. On one side it has prepared a PMO in its structure that contains a derivative of 4 - (aminofenil) -2.6 -difenilpirilio, which exhibits non-linear optical properties generated by the second harmonic excitation with a laser pulse of 1064 mm . The electroluminescent material contains in its structure a derivative of 9,10-diarilantraceno and emits light yellow having reached an efficiency of 0.5 cabdekas XM-2 and a conversion efficiencies and power in light of 3 lumenesxvatio-1. Finally, we have prepared two PMOs properties adsorbents. The first, is a PMO that due to the presence of units azobenceno in its structure, when irradiated with wavelengths suitable suffers isomerization E / ZoZ / E, which leads to significant changes in their ability to adsorb as it shows the different amount of colloidal gold to be adsorbed as the predominant lisómero Eo Z. The second group includes material urea in the PMO adsorbiendo iron in aqueous solutions with a constant sharing 700mlxg-1 and adsorption capacity of iron 0.19 mmolxg-1.

Author: BOHOYO GIL DIEDO.
Year: 2005.
University: EXTREMADURA [www.unex.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: The present research work, we have developed new methods of analytical determination of different antibiotics and active interest. The technique used to work in all analytical methods is the molecular luminescence. The compounds include certain antibiotics from the family of tetraciclimas and sulphonamides, anti-inflammatory and anticancer. The methods have been applied to show interest food (honey), formulations and animal biological fluids (urine and serum). We have used various strategic instrumentals (fluorescence, fotoinducida), chemical (sensitized fluorescence, lantáridos, means micelares, ciclodextrimas) and quimiométricas (techniques derived, multivariate calibration methods), for the establishment of methods of analysis. Among these methods include first order (partial least squares (PLS)), second order (Parallel Factors Analysis (PARAFAC) Decomposition Trilinear Alternada Autodescompuesta (SWATLD), Least Squares, Bilineares coupled with bilinearización, Residual (BLLS, RBL ), Least Squares Partial N-dimensionales (N-PLS), Partial Least Squares concatenated (Unfolded-PLS) and third order (Parallel Factors Analysis (PARAFAO), Least Squares Trilineares (TLLS / RTL) and Least Squares Partial Concatenados coupled with Trilinearización Residual (Unfolded-PLS/RTL). methods developed presented an undeniable interest from the point of view of its implementation agrifood and pharmacology, to allow additional analysis procedures simple and sensitive. Methods TLLS and unfolded-PLS/RTL, allowing the use of data from four routes have been developed in this work these methods represent an important advance in the methods guimiométricos of multivariate calibration, and a field investigation of very recent and current work in progress being the only alternative to PARAFAC data four tracks.

Author: NAVEA VÁZQUEZ SUSANA.
Year: 2005.
University: BARCELONA [www.ub.es].
Place of defense: FACULTAD DE QUÍMICA DE LA UNIVERSITAT DE BARCELONA.
Place of preparation: FACULTAD DE QUÍMICA (UNIVERSITAT DE BARCELONA).

Summary: This Doctoral Thesis has been directed to the improvement of overall strategies for monitoring and treatment of experimental data processing protein, from which it could get a better understanding of the structural information and the mechanisms that control. Examples of processes protein, in this paper we have studied the processes of folding, distortion and / or dimerización of various proteins model (alfa-lactoalbúmina, alfa-apolactoalbúmina and beta-lactoglobulina). These proteins have been induced by changes in temperature, pH or concentration of denaturing agents. For monitoring processes protein has been investigated the potential of spectroscopic techniques, such as molecular fluorescence, circular dichroism, infrared spectroscopy (medium and close) and mass spectrometry with ionization electroespray (ESI-MS) techniques we can observe conformational changes at different levels of protein structure, as well as the potential for their possible links. The experimental data have been analyzed using the method for resolving curves by alternating least squares (MCR-ALS), which allows for the mathematical resolution of the concentration profiles and spectra of the pure protein conformations in the process protein studied. The information contained in these profiles has enabled: * Modeling the mechanism of folding or denatured proteins. * Detect intermediate species that can not be isolated experimentally. * Modeling contributions of the protein in the presence of interfering signals that also evolve over the process under study. * Modeling species oligoméricas. Parallel to the study of protein processes has explored the possibility of using techniques espectroscópics simple (CD, or CD IR / ER) combined with tools quimiométricas for classification and elucidation of the secondary structure of proteins. For these studies have provided a CD database and IR-50 protein, known as RaSP50. In the classification of proteins have been used various methods of classification (supervised or unsupervised). The results show that the proteins that are classified on the basis of spectroscopic measures are the kinds of proteins alpha and beta. In contrast, proteins intermediate classes are not grouped by not presenting specific spectroscopic characteristics. For elucidation of the secondary structure of the reasons ordered (propeller alpha and beta sheet), the method of least squares regression intervals (iPLS). This method allows us to a selection of the CD spectral intervals and IR more related to the reasons for secondary structure propeller blade beta and alpha. From these selected spectral intervals, was conducted predicting the fraction of beta-sheet and alpha helix.

Author: BARCO CEPA MÓNICA.
Year: 2005.
University: BARCELONA [www.ub.es].
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: The microcistinas are a family of heptapéptidos monocíclicos produced by cyanobacteria of the genus Microcystis, Anabaena, Planktothrix (Oscillatoria) and Nostoc. In recent years it has significantly increased the interest in assessing the presence of these compounds in water source because of its high toxicity, and therefore the risk they pose to public health. Based on these considerations, the present study has been raised based on two main objectives. First, we intended to establish an analytical method for the identification and quantification of microcistinas in water samples and for that, in a first phase, we evaluated various methods for extracting the microcistinas contained inside the cells cyanobacterium (microcistinta intracellular) with a view to proposing a method that would allow the analysis of a large number of microcistinas intracellular. In addition, we are also developing a method of selective and sensitive analysis for the determination and identification of the different microcistinas present in water samples. To this end, we opted to use the cormatografía fluid coupled to mass spectrometry. The second objective was to study the presence of microcistinas in different surface commonly used as sources for obtaining drinking water in order to assess water quality and provide information on the real situation in our country. Finally, we have also proposed to evaluate the effectiveness of different water treatment processes for removing microcistinas.

Author: NOZAL MARTINEZ LEONOR.
Year: 2005.
University: CÓRDOBA [www.uco.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: The overall objective of this report was to assist in developing new strategies to improve the analytical potential of the analytical technique as Capillary Electrophoresis separation. We are trying to develop analytical methods for low cost, rapid response and high accuracy. By incorporating various online systems for commercial equipment Capillary Electrophoresis is intended to achieve a high degree of automation and robustness in the analytical methods proposed. We have addressed the following: * Link Systems continuous sample treatment equipment to commercial Capillary Electrophoresis to automate new analytical methodologies. * Development of a new type electroforética based on the formation of aggregates micelares in non-aqueous media. * Link supported liquid membrane and hollow fibers teams trading Capillary Electrophoresis for the direct introduction of the sample without pretreatment. The results of the investigations which are included in this report to be drawn the following general conclusions. 1, - With regard to methods based separations electroforéticas in aqueous media. 1.1-We have developed a new methodology, which allows rapid and reliable screening effect in the samples according to their contents in penicillin. The proposed methodology allows us to know the chemical form of administration. 1.2, has been developed and applied a method for determining tetracyclines in environmental samples, the waters of the river. The method is based on a system of preconcentration flow based on the solid phase extraction (SPE) coupled to a direct sales team of EC. 2-In regard to the methods electrophoretic made in non-aqueous media or microemulsionados. 2.1, has been demonstrated the efficacy of phase pseudoestacionarias in non-aqueous media to increase electroforética resolution. In particular it has been proposed for the first time the use of aggregates of surfactants as neutral phase pseudoestacionaria. The analytical potential of these systems has been demonstrated for the analysis of tetracyclines in water samples from the rivers. 2.2 - has been shown the possibility of using highly volatile organic solvents, such as hexane, the dissolution electroforética once stabilized and dispersed with the surfactant. The microemulsion hexane has enhanced resolution electroforética thereby simultaneous separation and quantification of three families of different antibiotics. 3 - With regard to the use of liquid membranes supported and / or hollow fiber coupled in the commercial team of EC. 3.1, have been described for the first time embedded systems processing systems based on sample extraction liquid phase would allow for the stages of purification and preconcentration in the electrophoretic own computer business without the intervention of the analyst. 3.2, has been developed into a system microextracción the liquid phase that inserted in the road team electrophoretic allows selectively extract the analytes of interest. The system is designed so that during the extraction process a positive electrode is introduced in the dissolution aceptora. The system has led directly to analyze the content in nitroimizadoles of homogenised of pig liver tissue without any treatment. 3.3, has been inserted (in-line) a unit microextracción liquid in the capillary electrophoretic. Specifically has identified non-steroidal anti directly in urine samples.

Author: RODRÍGUEZ GARCÍA JUAN CARLOS.
Year: 2005.
University: SANTIAGO DE COMPOSTELA [www.usc.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: In recent years, environmental pollution has become a major problem in industrialized countries and measure its scope in certain areas is a challenge for the scientific community because of the difficulties inherent in the sampling. One of the strategies is to evaluate indirectly through various indicators that accurately reflect the extent of pollution in a specific area. One of these indicators is possible that honey has been used in recent decades to monitor various pesticides, radionucleótidos and heavy metals in the environment. The quantification of heavy metals present in honey is a difficult task due to low concentrations they are in, which makes it necessary to develop methods with a low limit of detection techniques using highly sensitive. In the present work was carried out a study on the possible use of honey as a biomarker, depending on their metal content. It was therefore necessary to develop methods of determination by Atomic Absorption Spectrometry with Atomización Electrotérmica (ETAAS) technique sensitive enough to allow the identification of minority metals such as cadmium, lead, nickel, chromium and copper in honey Galicia, thus obtaining information on the influence anthropogenic estamatriz. Moreover, by Atomic Emission Spectrometry with Source Plasma Trailer Inductivamente (ICP-AES) were quantified major metals (iron, manganese, magnesium, calcium, potassium, sodium, lithium and zinc), which supplemented the information obtained previously. Once the determination of the metal content of a large number of samples of honey from the autonomous community of Galicia was necessary to use statistical techniques quimiométricas. These are techniques that enable process information and reach the right conclusions depending on the assumptions departida. Using techniques classification could be grouped according to their honeys metal content into two groups: honey from rural areas not charged, and honey from oznas industrial and urban impacted. Applying the technique for recognizing patterns based on multilayer neural networks, it was possible to correctly classify the samples with a margin of error of less than 10% in these two groups. The conclusion reached in this study was that developed 17 methodologies for the analysis of metals minority honeys by ETAAS. We conducted with the most appropriate methods for the content of cadmium, lead, copper, nickel and chromium from them, as well as the quantification of major metals. It was concluded after a study multivariate that there is a strong basis for using honey as a biomarker in Galicia based on their metal content.

Author: González Rodríguez Manuel Juan.
Year: 2005.
University: ALMERÍA [www.ual.es].
Place of defense: F.Ciencias Experimentales.
Place of preparation: Departamento de Química Analítica.

Summary: The use of pesticides is crucial in the control of pests in vegetable crops. The high application in agriculture, either as intensive extensive originates pollution of ecosystems and endangering people's health. To protect the health of consumers, many countries have established legal directives to control their levels in foods, through the maximum residue levels (MRLs). In this context, monitoring of pesticide residues in vegetables is now a priority in order to assess the quality of fruits and vegetables to prevent alterations in human health. This situation has prompted the EU to include food security among its policy priorities. It is especially important to improve quality standards and improve monitoring systems on the entire food chain, from farm or agricultural fields to the consumer. The EU intends to reach a fair balance between agricultural production competitive and respect for nature and the environment. The integration process is based on the introduction of measures to protect the environment in the various fields of community and entails the firm resolve to achieve consistency between environmental policy and agriculture. Therefore, the development of analytical methodologies reliable and secure, allowing environmental controls and food, are a necessity in today's society. The gas chromatography (GC) coupled with tandem mass spectrometry (MS / MS) is considered the main technique used for the analysis of pesticide residues due to the power of the GC separation, sensitivity, selectivity and ability to identification of the MS in tandem. GC-MS/MS in combination with the methods multirresiduo (MRM) is one of the most appropriate strategies and used in laboratories for analysis of pesticide residues, allowing control and measurement of a large number of analytes, at lower levels than the MRLs established. Currently, using a large number of active substances from different families: organochlorines, organophosphates, carbamates, tiocarbamatos, pyrethroids, fenilureas, triazinas, triazoles nitroanilinas, imidas, ect. Therefore there is a great variety of analytes with different characteristics (polarity, thermal stability, volatility, etc.). Which are of great interest to deal with their determination. The MRM must have analytical ability to respond to different families of compounds and therefore different properties. GC is the most widely used technique in MRM for their great capacity for separation, suitable for the analysis of volatile and semi-volatile compounds. At present, one of the trends of GC is the increased speed of analysis because of the economic impact that this entails. This report presents two alternatives for the development of methodologies for rapid analysis: the development of rapid methods GC Low Pressure (LP-GC) and the development of screening methods using MS-type triple cuadrupolo (QqQ- MS)

Author: RODRÍGUEZ BENCOMO JUAN JOSE.
Year: 2005.
University: LA LAGUNA [www.ull.es].
Place of defense: FACULTAD DE QUÍMICAS.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: It examines the content precursors of aroma and flavors in wine made with free varieties Malvasia, Listán White, Gual and Marmajuelo and is a classification in each range according to their importance organoleptica

Author: GIMÉNEZ IBÁÑEZ DIEGO.
Year: 2005.
University: BURGOS [www.ubu.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: The work falls within the scope of Quimiometría and, like any good method, explores and exploits the potential of multivariate calibration and multi to get useful information from the signals obtained from the modern analytical instrumentation, which provides a lot of action high quality. In particular, the pilot signals used in this work are spectroscopic signals (molecular absorption and fluorescence), and in either case it is concluded that the use of multivariate calibration or multi allows obviate the need to seek measures completely selective and specific. In fact, the use of expedited procedures, and with good economic detection capability as fluorescence excitación-emisión prove to be very efficient for the systematic analysis without complex pretratamientos of the sample, but with a multivariate calibration or (and) multi. As part of the systematic determinations (reference laboratories and control) the quality of an analytical determination is standardized. International agencies (such as ISO, IUPAC, FDA, etc.). As well as public institutions with the ability to establish legislation on toxic substances or hazardous to health or the environment have developed a methodology to evaluate the analytical methods. This is the case with the Commission's decision of August 12, 2002 of the European Union concerning the functioning of genetic analytical methods and the interpretation of results, which implements Directive 96/23/EC of the Council of the EU regulate the veterinary drug residues in foods of animal origin. In this regulatory context, it has been generalized concepts detection capability and analytical sensitivity when using a multivariate calibration / multi and has analyzed the impact of the ownership of second order on these figures of merit. It has also explored the effect on the analytical determinations include various sources of variability in usual measures (analyst, time, not calibrated substances present in the sample, and so on.). All this has led to the establishment of a functioning practical approaches to optimize utilization of the property of second order to achieve the highest quality in the analytical determination.