Last week, we discussed the loss of reduction efficiency in cadmium coils caused by nitrate contamination in ammonium chloride. This week we are examining metal contamination and cadmium coil efficiency.
This type of contamination occurs in the sulfanilamide solution. Of course, sulfanilamide solution contains N-naphthylethylenediamine dihydrochloride which serves to bind heavy metals. If metal exists in too high a concentration, the oxidation state of the surface of the cadmium can be affected, therefore causing a loss in reduction efficiency. The possibilities are many and each laboratory’s individual purchasing and storage characteristics make this a very difficult hurdle to overcome. We suggest that if new solutions are made to troubleshoot problems, try different vendors and/or lot numbers of the chemicals used for analysis. This will cover whether contamination exists in any of the chemicals as a potential cause of loss in coil reduction efficiency.