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This worlk proposes a rapid, sensitive and accurate flow-batch digital image colorimetric (FB-DIC) system to zinc oxid determination in ointments. The method was based on the reaction between Zn(II) ions and zincon at pH = 9.0. The Zn(II)-zincon complex was formed and detected in the mixing chamber. It was designed with two opposite glass windows: one for the webcam and other for the ultra-bright LED. Absorbance was calculated by the norm of the vector in the RGB space. The method had a linear range between 1.0-8.2 mg L–1 with R2 = 0.9998 (n=8) and limit of detection estimated as 5.7 mg L–1. The relative standard deviation (RSD) and sample throughput were estimated at 0.06% and 109 samples h-1, respectively. Ointment commercial samples were analyzed by FB-DIC and the refference method. The results shown no statistically significant difference between them, when was applied the paired t-test at the 95% confidence level. According to green analytical chemistry (GAC) principles the FB-DIC system can be considered eco-driendly due to its low samples and reagents consumption as its low waste generation.

Neste trabalho foi desenvolvido um sistema de multicimutacao em fluxo para determinacao de diclofenaco de sodio, acido acetilsalicilico e fluoretos em injetaveis, comprimidos e aguas de torneira, respectivamente. Para diclofenaco de sodio o metodo usado foi baseado em sua reacao com permanganato de potassio (20 - 80 mg L -1 ). Para acido acetilsalicilico o metodo usado foi baseado na reacao de Trinder apos hidrolise alcalina do analito (25 - 100 mg L -1 ). Para ions fluoreto o metodo usado foi o bem conhecido SPADNS (0.4 - 1.6 mg L -1 ). Resultados foram comparados com seus respectivos metodos de referencia e, aplicando o teste- t emparelhado, nenhuma diferenca estatisticamente significativa foi verificada entre eles ao nivel de confianca de 95%. Apos a otimizacao das variaveis do sistema analitico, ele foi capaz de analizar 80, 72 e 68 amostras h -1 contendo diclofenaco de sodio, acido acetilsalicilico e fluoretos, respectivamente com geracao de residuos reduzida de acordo com os principios basicos da quimica verde.