Practical evaluation of ion chromatography methods developed by an expert system

As ion chromatography (IC) has matured as an analytical technique, it has become more automated. IC has not seen the abundance of automated method optimisation techniques that are provided to conventional chromatography. The authors have previously attempted to fill this gap by developing an expert system that can give comprehensive advise on IC method conditions for a variety of IC separation mechanisms. The expert system can give advice on several IC method conditions, including mobile phase, column, pH, mechanism, post column reactors, suppressor use and gradient applicability. The work in this paper describes the evaluation of the expert system including a practical evaluation of the methods, suggested by both the expert and the expert system, by running the full methods on an ion chromatograph and validating the methods. One of the features of IC is that more than one method can be suitable for a given set of analytes, differences were therefore expected in the methods suggested by the expert and those suggested by the expert system. The aim of the work presented here was to find if the expert system methods could perform in practice as well as those of the expert. Results of the validation of sensitivity, precision and limits of determination are given. The paper highlights some of the problems with expert systems developed using a database, as opposed to one developed by an expert.