FRUCTOSE-6-PHOSPHATE KINASE IMMOBILIZED ON CONTROLLED-PORE GLASS AS A SUBSTRATE FOR SELECTIVE SEPARATION OF ANTIMONY(III)

Fructose-6-phosphate kinase immobilized on controlled-pore glass and packed in a glass microcolumn was used for the selective separation and preconcentration of Sb(III). Results obtained for mixtures of trivalent and pentavalent antimony showed that Sb(III) can be selectively separated from Sb(V) after retention by the enzyme and elution with a 3% v/v lactic acid solution. After the elution step Sb(III) was determined by electrothermal atomic absorption spectrometry. An enrichment factor of 5 was achieved. Recovery studies of Sb(III) in de-ionized, tap and sea-water gave values of around 75 +/- 5% without any need to control the pH or temperature. The immobilized enzyme retains its activity for at least 200 elution cycles.