Determinação por cromatografia gasosa de alguns poluentes halogenados pouco volateis em agua

Orientador : Antonio Luiz Pires ValenteDissertação (mestrado) - Universidade Estadual de Campinas, Instituto de QuimicaMestrad

Feasibility of Use of the Microwave Induced Plasma Atomic Emission Detector as a Compound Independent Detector for Quantitative Chromatographic Analysis

The independence of the response of a Microwave Induced Plasma Atomic Emission Detector (GC-MIP) for Gas Chromatography with the chemical structure of the analyte has been exploited using as teste samples nine organochlorine compounds. With signal monitoring at the chlorine 479.5 nm emission line and after proper adjustment of the operational conditions of the GC-MIP the agreement of the detector response for the nine compounds was of 8.5% or less, which is adequate for the use of the compound-independent calibration method. It is proposed that the reliability of the quantitation after applying the compound-independent calibration methodology may be enhanced if a set of calibration compounds is used instead of a single calibration compound.Foi estudada a independência da resposta de um Detector por Emissão Atômica Induzida em Plasma de Microondas utilizando-se nove compostos organoclorados como amostra de teste. Com ajuste apropriado das condições operacionais do equipamento, monitorando os sinais na linha de emissão do cloro em 479,5 nm, para os nove compostos foram obtidas respostas concordantes ao nível de 8,5% ou menos, o que é adequado para uso do método de calibração independente do composto. Propõe-se que a confiabilidade da quantificação com a metodologia de calibração independente do composto pode ser melhorada, se um conjunto de compostos é usado em lugar de um único composto de calibração.1721Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Modification of a glass micro-extractor aiming to enrichmentt of traces of water contaminating organochlorinated pesticides and their quantitative gas chromatographic analysis

Two models of a glass micro-extractor were constructed after modification of a model proposed in the literature. The two models were used for the simultaneous extraction and enrichment of organochlorinated pesticides from aqueous matrixes to an organic solution appropriate for the gas chromatographic analysis of the pesticide. It was established that the performance of one of the modified micro-extractors permits the pre-concentration of the pesticides to a level that allow their quantitation at the trace level with electron capture detection. It is thus concluded that the glass micro-extractor is a suitable tool for the sample preparation step in the gas chromatographic analysis of environmental pollutants of the class of pesticides.109113Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Exploiting green sorbents in rotating-disk sorptive extraction for the determination of parabens by high-performance liquid chromatography with tandem electrospray ionization triple quadrupole mass spectrometry

© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim In this study, the viability of applying cork and montmorillonite clay modified with ionic liquid as biosorbents in the rotating-disk sorptive extraction technique was investigated. Specifically, this was aimed at the determination of methyl paraben, ethyl paraben, propyl paraben, and isobutyl paraben, with separation/determination by high-performance liquid chromatography coupled with mass spectrometry. The optimization of the method for both biosorbents was performed using multivariate procedures. The extraction efficiencies for the target compounds in aqueous matrices were compared to those obtained using the commercial sorbent Octadecil Silano-C18. The optimum extraction conditions for both natural sorbents were the use of an ammonia solution (pH 10) as desorption solvent and an extraction time of 30 min. The proposed methods show limits of quantification of 0.8 μg/L for cork, 3.0 μg/L for montmorillonite clay and 6.0 μg/L for Octa