On-line solid phase extraction of Cd from protein fractions of serum using oxidized carbon nanotubes coupled to electrothermal atomization atomic absorption spectrometry

This work presents a sensitive and accurate method for Cd determination in serum protein fractions separated by cellulose acetate electrophoresis (CAE). The determinations were carried out by on-line solid phase extraction using oxidized carbon nanotubes coupled to electrothermal atomization atomic absorption spectrometry (ETAAS). The detection and quantification limits were 10 ng L− 1 and 35 ng L− 1 respectively with a precision of 4.0% as relative standard deviation. This procedure joined the simplicity of protein separation by CAE, the preconcentration properties of solid phase extraction using ox-CNT and the excellent sensitivity attainable by ETAAS. The method was applied to samples with biological relevance (humans and experimental rats). Our work demonstrated that Cd could be determined in serum protein fractions separated by electrophoresis with good accuracy using the proposed method.