In this article, the influence of the monomers on the extraction efficiency and the effect of the... more In this article, the influence of the monomers on the extraction efficiency and the effect of the addition of surfactants during the synthesis have also been considered. The sorption capacity of the resulting nanocomposites has been evaluated, in the dispersive micro-solid phase extraction format, by determining that of six benzophenones in water using ultra performance liquid chromatography (UPLC) combined with photodiode array detection. Under the optimum conditions, the limits of detection were in the range of 0.5-4.3 ng/mL and the repeatability, expressed as the relative standard deviation (RSD), varied between 1.5% and 5.6%. The proposed method has been applied for the analysis of real water samples, providing relative recoveries in the interval of 84-105%
The extraction yield of a microextraction technique depends on thermodynamic and kinetics factors... more The extraction yield of a microextraction technique depends on thermodynamic and kinetics factors. Both of these factors have been the focus of intensive research in the last few years. The extraction yield can be increased by synthesizing and using novel materials with favorable distribution constants (one of the thermodynamic factors) for target analytes. The extraction yield can also be increased by improving kinetic factors, for example, by developing new extraction modes. Microextraction techniques are usually non-exhaustive processes that work under the kinetic range. In such conditions, the improvement of the extraction kinetics necessarily improves the performance. Since the extraction yield and efficiency is related to how fast the analytes diffuse in samples, it is crucial to stir the sample during extraction. The stirring can be done with an external element or can be integrated with the extraction element in the same device. This article reviews the main recent advances in the so-called extraction/stirring integrated techniques with emphasis on their potential and promising approaches rather than in their applications.
In this article, the influence of the monomers on the extraction efficiency and the effect of the... more In this article, the influence of the monomers on the extraction efficiency and the effect of the addition of surfactants during the synthesis have also been considered. The sorption capacity of the resulting nanocomposites has been evaluated, in the dispersive micro-solid phase extraction format, by determining that of six benzophenones in water using ultra performance liquid chromatography (UPLC) combined with photodiode array detection. Under the optimum conditions, the limits of detection were in the range of 0.5-4.3 ng/mL and the repeatability, expressed as the relative standard deviation (RSD), varied between 1.5% and 5.6%. The proposed method has been applied for the analysis of real water samples, providing relative recoveries in the interval of 84-105%
The extraction yield of a microextraction technique depends on thermodynamic and kinetics factors... more The extraction yield of a microextraction technique depends on thermodynamic and kinetics factors. Both of these factors have been the focus of intensive research in the last few years. The extraction yield can be increased by synthesizing and using novel materials with favorable distribution constants (one of the thermodynamic factors) for target analytes. The extraction yield can also be increased by improving kinetic factors, for example, by developing new extraction modes. Microextraction techniques are usually non-exhaustive processes that work under the kinetic range. In such conditions, the improvement of the extraction kinetics necessarily improves the performance. Since the extraction yield and efficiency is related to how fast the analytes diffuse in samples, it is crucial to stir the sample during extraction. The stirring can be done with an external element or can be integrated with the extraction element in the same device. This article reviews the main recent advances in the so-called extraction/stirring integrated techniques with emphasis on their potential and promising approaches rather than in their applications.
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