Um método espectrométrico de emissão em chama baseado em imagens digitais para determinação indireta de fármacos e determinação simultânea de sódio e cálcio

Abstract

In this work the potential of the Digital Image-Based Flame Emission Spectrometry (DIB-FES) is demonstrated through two completely separate applications. The first one consists in the indirect determination of three drugs in injectable form: sodium dicofenac, sodium dipyrone and clacium gluconate and the second in the combination of DIB-FES with Multiple Linear Regression (MLR) for the simultaneous determination of sodium and calcium in powder milk. Up to the present moment the literature does not report the use of traditional FES in: indirect determination of organic substances, simultaneous determination of analytes using a unique detector and overcoming the problem of spectral interference. In DIB-FES digital images of the flame are captured by webcam in its oxidant region (2,5 cm over the burner of the flame photometer) and are associated with the radiation emitted by metals present in the air-butane flame. Based on Red-Green-Blue (RGB) colour system, univariate and multivariate calibration models were developed, which were validated and then applied to real samples. In each application the results were compared with the results obtained by their respective reference methods. There were no statistically significant differences between the results when the paired t-test at the 95% confidence level. The estimated precision was better than the respective reference methods and accuracy was assessed by high values of bias and recovery rates between 97 and 104% in the two applications.