ONLINE PRECONCENTRATION OF ALUMINUM WITH IMMOBILIZED CHROMOTROPE 2B FOR THE DETERMINATION BY FLAME ATOMIC-ABSORPTION SPECTROMETRY AND INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY

A new and rapid on-line preconcentration and matrix separation method is described for the determination of aluminium by name atomic absorption spectrometry (FAAS) and inductively coupled plasma mass spectrometry (ICP-MS). The method is based on selective retention of aluminium in a microcolumn packed with Chromotrope 2B immobilized on AG 1-X8 ion exchange resin. All the variables that affect the efficiency of aluminium retention and elution from the microcolumn have been investigated. The resulting method is rapid, sensitive and selective. For collection times of 10 and 2 min at a flow rate of 1 ml min(-1) the detection limits are 10 and 0.1 ng ml(-1) for FAAS and ICP-MS, respectively. The proposed method, which is highly sensitive and selective, was successfully applied to determine aluminium in tap water and dialysis solutions.