Desenvolvimento de métodos cromatográficos limpos para a determinação de compostos orgânicos explorando ambientes micelares

Abstract

In this work is proposed the separation and determination of organic molecules presenting different polarities by using the high performance liquid chromatography (HPLC) associated to the micellar medium, avoiding the usage of hazardous reagents as mobile phase. The determination of triazine herbicides in water, soil and food samples and the determination of textile dyes in industrial effluents are selected as applications, always using a RP-18 column as stationary phase, which was temporary modified by the constituents of the mobile phase during the analysis, increasing the possibilities of the usage of the strategy and become possible the development of green analytical methods exploiting the HPLC. The developed analytical method for triazine herbicides determination used 2.25 % (w/v) of SDS, 25.0 % (v/v) of ethylic alcohol, 50.0 mmol/L of NH4Cl and 0.100 mol/L (pH 7.0) phosphate buffer solution as mobile phase and RP-18 column as stationary phase. The method was selective, sensitive, robust, simple and present high analytical frequency with retention times of 11.4, 15.6 and 24.4 min and detection limits of 100, 100 and 150 µg/L for simazine, atrazine and ametrine, respectively. The results are in agreement to those obtained by the conventional HPLC method that uses expensive and toxic organic solvents. The developed analytical method for textile dyes determination used 1.0 % (v/v) of Triton X-100, 20.0 % (v/v) of ethylic alcohol and 5.00 mmol/L of phosphate buffer solution (pH 7.0) as mobile and a RP-18 column as stationary phases. The method was simples, selective, sensitive, robust and present high analytical frequency with retention times of 2.0,2.9 and 5.1min and detection limits of 0.40, 0.80 and 0.80 mg/L for Yellow Procion H-4R, Red Procion H-E7B and Brilliant Blue Remazol, respectively. The recovery tests were considered satisfactory as for all the samples were obtained almost 100 % for analyte recovery.