Exploratory analysis of L’vov platform surfaces for electrothermal atomic absorption spectrometry by using three-way chemometric tools Original Research Article

An exploratory analysis of the effects of permanent (Zr) and conventional (Mg and a mixture of Pd+Mg) chemical modifiers on L’vov platforms for electrothermal atomic absorption spectrometry (ETAAS) was performed in this work by using two chemometric tools. Twelve L’vov platforms were used for Al, Cd and Pb determination in biological slurry samples. For each platform, a different combination of chemical modifier, number of heating cycles and determined analyte was employed. The morphology of the platforms was evaluated using scanning electron microscopy (SEM) and the obtained data was analysed with image principal component analysis (image PCA). The results allowed differentiating the platform treated with Mg from the other platforms. In addition, eight residual species (P, S, Ca, Ti, Fe, Zr, Hf and Pd) distributions were obtained by using micro synchrotron radiation X-ray fluorescence (μSRXRF) in the same platforms for 100 points across the horizontal axis. These data were modelled with orthogonal constrained PARAllel FACtor analysis (PARAFAC) and a global characterisation of the platforms was achieved. Four platforms presented a particularly behaviour, being so different among themselves, that it was necessary one specific factor (1–4) to model each one. Factor 5 demonstrated that two platforms presented a similar behaviour characterised by high Ca and, to a lesser extent, Ti content. Finally, factor 6 modelled the correlated behaviour of five platforms characterised by Zr content. It was also observed that the platform morphology has a good connection with the residual species found in its surface. This kind of study can open a vast field to exploratory analysis of L’vov platforms in ETAAS.