Orthogonal array design for optimizing the capillary zone electrophoretic analysis of heterocyclic amines

Orthogonal array design (OAD) has been applied to the optimization of the capillary zone electrophoretic (CZE) analysis of heterocyclic amines (HCAs), carcinogenic and mutagenic compounds that are found in cooked foods. The factors affecting separation efficiency, such as the pH of the buffer solution, organic modifier and buffer concentrations, the applied potential, and the operating temperature, are studied in two steps under OAD. In the first experiment, each variable is tested at two levels using an OA16 (2(15)) matrix to determine the most important factors and the interactions between them. Based on the results of the first step, the second experiment is implemented according to a three-level OAD with an OA9 (3(4)) matrix, in which more exact values for the important variables are chosen. Finally, the determined optimum conditions for the CZE analysis of the 12 HCAs are applied and evaluated.