EVALUATION OF A MATHEMATICAL-MODEL TO SIMULATE DYNAMIC-RESPONSE OF TUBULAR POTENTIOMETRIC SENSORS IN FLOW-INJECTION SYSTEMS

Potentiometric detectors based on ion-selective electrodes are special ly suited to flow measurements because of their low cost and high sele ctivity. Simultaneously in flow analysis the use of tubular-electrode configuration seems ideal as the flow characteristics can be kept cons tant throughout the system. The design of very simple manifolds, which increases the robustness and the system reliability, is constrained b y the knowledge of the influence of hydrodynamic parameters in the det ector response. With the aim to optimize the design of this kind of sy stems a mathematical model, that simulates the response of tubular pot entiometric detectors in flow-injection systems, has been developed an d tested. Results provided by simulation are compared with experimenta l ones, and the model capabilities are discussed.