IMMOBILIZED CHLOROXINE AS A PRECONCENTRATION REAGENT FOR ATOMIC-ABSORPTION SPECTROMETRY

A now injection system combining on-line preconcentration with immobil ized chloroxine and spectrophotometric detection was developed for tra ce metal determination. The chloroxine was immobilized onto a silanize d control pore glass substrate which showed excellent stability. The r eagent was packed into a minicolumn and used to preconcentrate Cu2+, Z n2+, Cd2+, Co2+, and Pb2+ The enhancement in sensitivity was on the or der of 49-136 times better than that for direct injection, using a 5-m l sample with a sampling rate of 20 h(-1). (C) 1996 Academic Press, In c.