Influence of different volume ratios on the isodispersion point in sequential injection analysis

The importance of zone penetration can be ascribed to the fact that this influence has a dramatic effect on the surface area over which a concentration gradient exists and therefore over which axial mixing takes place. In this study different volume ratios were used to illustrate the shift of the isodispersion point due to the difference in concentration gradients in sequential injection analysis (SIA). The position of penetration and the sequence of introduction of samples and reagents for different sample and reagent volume ratios in a total constant volume has a major influence on the response of the final peak profile. The response of the final peak profile depends largely on the kinetics involved in both the ascending and tailing parts of the sample and reagent zones at the isodispersion point.