A new portable micropipette tip-syringe based solid phase microextraction for the determination of vanadium species in water and food samples

Simple, rapid and miniaturized portable micropipette tip-syringe solid phase microextraction method was developed for speciation of vanadium in water and food samples. Tetra ethylene pentamine functionalized multiwalled carbon nanotubes were synthesized and packed in micropipette tip-syringe system. The surface morphology of adsorbent was characterized, and the effective factors that influence the efficiency of developed method such as pH, amount of adsorbent, concentration of acid solution for desorption cycles were studied. The V(V) could be adsorbed on the modified adsorbent surface with tetra ethylene pentamine, while V(IV) could not be retained. The assay of V(IV) was based on subtracting values of V(V), from total vanadium. The extracted total vanadium and V(V) were injected directly into the electrothermal atomic absorption spectrometry for analysis. Enhancement factor and detection limit were found 50 and 0.008 μg L⁻¹, respectively. Accuracy of the method was checked by analysis of certified reference materials. The developed method was applied to water and food samples.