Fast and reliable non-chromatographic speciation analysis of tin in waters assisted by ion imprinted polymers for SnII and tributyltin

Fast and reliable non-chromatographic speciation analysis of tin in waters assisted by ion imprinted polymers for SnII and tributyltin

Poster

Rositsa Staykova, Tanya Yordanova
Faculty of Chemistry and Pharmacy, Sofia University "Saint Kliment Ohridski", Sofia

This work is focused on the development of non-chromatographic method for speciation analysis of tin in waters based on solid-phase extraction with ion-imprinted polymers (IIPs). IIPs were synthesized and utilized as sorbents for selecive solid-phase extraction of SnII and tributyltin (TBT). Methacrylic acid (monomer), trimethylolpropane trimethacrylate (cross-linker), 2,2’-azobisisobutyronitrile (initiator), acetonitrile (solvent), SnII and TBT (template species) and different chelating ligands (pyrrolidine dithiocarbamate, thionalide and dithizone) were used in the preparation of the ion-imprinted polymers. Three IIPs for SnII and one for TBT (with dithizone) were produced and characterized by elemental analysis in order to evaluate the extent of incorporation of the ligands in the recognition sites. The main parameters of extraction procedure, i.e. pH of samples, time for quantitative retention/desorption, type/concentration of the eluent solutions were investigated in a batch mode and the optimal conditions were defined. In the case of the IIPs for SnII, quantitative sorption was achieved at pH in the range 6 – 9 for 30 min, while retention of TBT was 97.1% at pH 9 for 35 min. Excellent elution of SnII was performed by using of 0.25 M L-cysteine, acetic acid (1 mol/L) was selected for desorption of TBT. Selectivity of the IIPs was demonstrated by separation of the target species in the presence of SnIV. Analytical procedure for non-chromatographic speciation analysis of tin was proposed and applied to bottled and natural waters with very good reproducibility and accuracy. Acknowledgement: The authors gratefully acknowledge the financial support provided by Sofia University Scientific Foundation (Grant No. 80-10-149).
Keywords: Tin, ion-imprinted polymers, solid-phase extraction, speciation analysis