2019-09-132022-04-262022-04-262019-08-08SIQUEIRA, A. G. Desenvolvimento de um método de extração em fase sólida in situ para determinação de Cr(III) em infusão de fitoterápicos. 2019. 73 f. Dissertação (Mestrado em Química) - Universidade Federal de Goiás, Catalão, 2019.http://repositorio.ufcat.edu.br/tede/handle/tede/10014This work presents the development of an in situ solid phase extraction method (SPE-ISS) for the determination of chromium (III) in herbal infusion samples using flame atomic absorption spectrometry (F AAS). Thus, in order to evaluate the inorganic composition of medicinal plant samples (calendula, chamomile, carqueja, green tea, leather hat, melissa and passiflora) we used the EDXRF (Dispersive Energy X-ray Fluorescence). the presence of plant essential metals in addition to toxic metals. Subsequently, a quantitative analysis of some metal ions was performed in infusion samples prepared from these plants, and Fe(III) was the only one found in considerable concentration, while Pb(II), Cr(III), and Cd(II) presented concentrations below the detection limit of the technique. Therefore, it is necessary to develop extraction and preconcentration methods that allow the determination of Cr(III) simply and safely, even when present in low concentrations. In this work, the SPE-ISS method was optimized by multivariate techniques, and the results showed that the formation of the Cr-PAN complex is favored at pH 9.5, with the complexant at 0.18 mmol L-1 concentration. For optimization of solid phase formation and extraction, factorial design and response surfaces were used, which pointed to the use of CTAB as phase transfer agent, NaClO4 0.26 mol L-1 as ionic pairer and agitation time of 7.5 minutes. Studies of possible interferents indicated negative interference of the metallic ions Al(III), Zn(II), Fe(III) and Ca(II). The analytical performance was evaluated by the parameters, preconcentration factor, detection limit (LD) and limit of quantification (LQ) and the values ​​found were 1.66 μg L-1 and 5,5 μg L-1, respectively. The intra-day and inter-day precision (RPD) was 0.001% and 0.0004%, respectively, being the linear range of the method from 250 to 5000 μg L-1, presenting the potential to determine low chromium concentrations. Finally, the accuracy of the method was evaluated from analysis of certified reference water material (APS-1071), as well as recovery tests on water samples and herbal infusions 77.60 - 116%.application/pdfAcesso AbertoFitoterápicosExtraçãoIn situF AASPhytotherapeuticsExtractionIn situF AASQUIMICA::QUIMICA ANALITICADissertação