Interinstrumental Transfer of a Chiral Capillary Electrophoretic Method: The Use of Robustness Test Information to Overcome Differences in Detector and Data-Handling Specifications

Capillary electrophoresis has been widely used as chiral separation technique, applying chiral selectors that are added to the background electrolyte. The advantages of capillary electrophoresis as separation technique are its flexibility, low cost, and high separation efficiency. This study is part of a research project, where guidelines are defined to facilitate interinstrumental method transfer of capillary electrophoretic methods, which is one of the major drawbacks of capillary electrophoresis. Another drawback is the lower sensitivity compared to liquid chromatographic methods. Improving and maintaining the sensitivity are the reason why focus should be put on the interinstrumental differences between detector settings. The aim of this study was to determine when adaption of the detector settings during interinstrumental method transfer was needed. The chiral separations of two betablockers were selected as case studies. The influence of detector parameters, such as data acquisition rate, bandwidth, and filter, on sensitivity responses, such as peak area, height, and width, was evaluated by means of robustness tests performed on two capillary electrophoresis instruments. The statistically significant parameters were identified and non-significance intervals determined. To maintain or optimise the obtained sensitivity, the information gathered from the robustness test was further incorporated in guidelines developed to facilitate interinstrumental analytical method transfer of capillary electrophoretic methods.