Capillary zone electrophoresis of soil humic acid fractions obtained by coupling size-exclusion chromatography and polyacrylamide gel electrophoresis.

Capillary zone electrophoresis (CZE) was used for characterisation of soil humic acid (HA) fractions obtained by coupling size-exclusion chromatography with polyacrylamide gel electrophoresis, on the basis of their molecular size and electrophoretic mobility. CZE was conducted using several low alkaline buffers as background electrolyte (BGE): 50 mM carbonate, pH 9.0; 50 mM phosphate, pH 8.