Desenvolvimento de procedimentos analíticos para determinação de analitos em amostras de interesse ambiental, alimentício e farmacêutico utilizando espectrofotometria derivativa e espectrofluorimetria

Abstract

In this working is shown the development of three analytical procedures: The first procedure was based on the first-order derivative spectroscopy for the simultaneous determination of BHA, BHT without previous separation, using the zero-crossing technique in mayonnaise and salad dressing samples. The procedure showed a linear range varying between 5.55x10-5 to 3.33x10-4 mol L-1 for quantification of BHA. The linear range for BHT determination varying between 9.08x10-5 to 5.44x10-4 mol L-1. The detection limit and quantification limit obtained for the proposed procedure were 2.53x10-5 mol L-1 and 6.67x10-5 moles L-1, respectively for BHA, and 4.77x10-5 mol L-1 and 1.44x10-4 mol L-1, respectively for BHT. The second developed procedure employs spectrofluorimetry for determination of ketoconazole in different matrices (river water samples and tablets). The calibration curve showed linearity between 5.00x10-7 to 1.00x10-5 mol L-1, and a detection limit of 1.36x10-7 mol L-1. The recoveries ranging from 75.2 to 98.5% for drug samples and from 75.6 to 108% for river water samples were obatined. The third spectrofluorimetric procedure developed was based on the fluorescence of bisphenol-A. The procedure was developed to determine BFA in river water samples. The calibration curve obtained was linear between 7.50x10-7 to 1.00x10-5 mol L-1. the detection limit of 7.37x10-7 mol L-1 and recoveries ranging from 70.5 to 106% for river water samples were obtained.