Interference by other halides in the automation of chloride. Contributions to the general methodology of continuous flow systems.

An investigation was undertaken to study the factors which cause grossly elevated values in an automated procedure for chloride when the sample is contaminated with bromide. The questioned mercuric thiocyanate method of the autoanalyzer was compared to a similar system utilizing mercuric 2, 4, 6-tripyridyl-s-triazine as a substitute ligand source in the chloride exchange system. It was determined that variation in the rate of dialysis of the halides was one factor which provided a compensating error apparently owing to a graded increase in rate of diffusion with an increase in hydrated ion size. The variable release of thiocyanate by the different halides as compared to the equivalent release of ligand from the tripyridyl-s-triazine (TPTZ) complex by the halides was another important factor. When both factors were considered, the non-linear elevated results could at least be partially explained.