Therefore, there was no need for the preparation and optimization of the extraction procedure using standard alcoholic solutions to simulate the matrix to be studied (white wine) since the alcohol content of the analyzed samples ranged from 9.5% to 13.5%. Thus, the proposed extrac- tion method was efficient for the extraction of pesticides, both in aque- ous and in alcoholic solutions, with a concentration of ethanol up to 15%.
Given the knowledge that toluene is immiscible in water and completely miscible in ethanol [24], worth pointing out that during testing to evaluate the influence of alcohol content in the extraction of pesticides, it was observed that with increasing ethanol concentration of the solution containing the pesticide standards occurred solubiliza- tion of a portion of the microdrop of toluene, which can hamper the ex- traction procedure. This can be observed by the examining the phase diagram of a ternary system compound by ethanol–toluene–water, which is observed that the toluene is solubilized completely, in binary