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En esta Memoria se proponen una serie de mejoras científico-técnicas relativas al desarrollo y aplicación de sistemas automatizados en flujo para el análisis de moléculas de diferente índole en los campos farmacológico y agroalimentario, plasmadas en las nueve publicaciones científicas que se presentan, mostrando su versatilidad y aplicabilidad analítica. Se ha puesto especial hincapié en incrementar el nivel de automatización de los sensores en flujo descritos hasta la fecha, perfeccionando el uso de los sistemas multiconmutados en flujo en este tipo de sistemas analíticos. Se han empleado técnicas de detección luminiscentes, incidiendo especialmente en aquellas que han permitido un incremento en la selectividad y cuyo desarrollo hasta la fecha ha sido reducido, como es el caso de la Fluorescencia Inducida Fotoquímicamente. Igualmente, se han utilizado nanopartículas fluorescentes para poder llevar a cabo la determinación luminiscente de analitos que no presentan fluorescencia nativa. In this Report, several scientific/technical improvements concerning the development and the application of automated flow systems are proposed. The systems developed were applied to the analysis of molecules of different nature in the pharmacological and agri-food fields, showing its versatility and its analytical applicability. The research here described gave origin to nine scientific publications in scientific international journals. Special emphasis was placed on increasing the level of automation of the flow sensors described to date, particularly improving the potential of multicommutated flow injection analysis methods. The selection of luminescent detection techniques was performed by paying special attention to two aspects: a) increasing the selectivity of the analytical methods; b) the use of detection techniques that have been underused in flow systems, such as Photochemically Induced Fluorescence. Likewise, fluorescent nanoparticles have been used to carry out the luminescent determination of analytes that do not exhibit native fluorescence. Tesis Univ. Jaén. Departamento Química Física y Analítica. Leída el 26 de noviembre de 2018.

[EN] In this Memory it is showed the development of ten spectroscopic continuous flow sensors for the automatic determination of organic and inorganic species of environmental and pharmaceutical interest. These sensors have been classified according to the developed methodology in sensors with or without renovation of the sensing surface.Three flow sensors without renovation of the sensing surface ha ve been developed using this methodology, one of them uses spectrophotometric detection and two of them spectrofluorimetric detection, based on the measurement of the absorbance in UV region or the intrinsic fluorescence of the analytes. In all these cases it is not necessary previous derivation reactions.The seven developed sensors with renovation of the sensing surface are based on the concept of Bead Injection Spectroscopy. The use of this methodology is justified when the species of interest is strongly retained on the sensing surface and the regeneration of the support is not possible in suitable conditions or becomes extraordinarily difficult. The methodology used in these seven sensors is based on the injection of an exact volume of a homogenous beads suspension in a flow injection analysis system with spectroscopic detection. The beads (solid support) are loaded in the flow cell placed in the detection zone of a nondestructive spectroscopic detector. At the end of the analysis, the beads are discarded by reversing the flow and instantaneously transported out of the system, being replaced the sensing surface after each measurement.In all cases, a great study of the experimental variables that can affect this type of sensors has been performed. Next, the sensors were calibrated for the corresponding analytes, finding a calibration equation that allowed relating the values of the analytical signals with the concentration of the sample. The method used in all the cases was the univariante ca libration. Studies of interferences were made to know the response of the sensor in presence of the organic and inorganic compounds that usually accompany the analytes in the rea l samples. In the case of serious interferences occurring, appropriate modifications for their elimination were designed. Finally, the proposed sensors were applied to the determination of these analytes in samples of different nature. The results confirm the validity of the proposed sensors., Tesis Univ. Jaén. Departamento de Química Física y Analítica. Leída el 21 de enero de 2005