Patent ID: 7144735

Claim:
A method of analyzing trace metals in solution, comprising: providing a sample channel separated from a first carrier solution channel by a first anion exchange membrane and separated from a second carrier solution channel by a second anion exchange membrane; flowing a sample through the sample channel, wherein the sample includes an acidic matrix and at least one trace metal to be detected; flowing a first carrier solution through the first carrier solution channel; flowing a second carrier solution including a metal-complexing reagent through the second carrier solution channel so that the metal-complexing reagent diffuses through the second ion exchange membrane into the sample; and providing an electrical potential to assist diffusion of an anionic form of the acidic matrix through the first anion exchange membrane into the first carrier solution channel and to assist diffusion of hydroxide ions from the second carrier solution through the second anion exchange membrane into the sample to neutralize at least a portion of the acidic matrix, whereby the diffused metal-complexing reagent in the sample complexes with the at least one trace metal such that the at least one trace metal doesn't combine with the hydroxide ions.