ELIMINATION OF PARASITIC SIGNALS CAUSED BY GAS-BUBBLES BY INTEGRATINGSEPARATION AND DETECTION IN CONTINUOUS-FLOW SYSTEMS

A novel, additional advantages of flow-through chemical sensors based on the integration of adsorption process and photometric detection is presented. It consists of the avoidance of the well-known parasitic si gnals caused by gas (CO2, SO2, N2) bubbles inserted or generated ''in situ'' in a continuous flow-manifold coupled on-line with a sensor. A systematic study of the experimental variables allows to establish the optimal conditions to achieve the complete disappearance of these und esirable signals without any electronic signal manipulation. This is r ealised by packing a solid material (C18 bonded silica or SP Sephadex beads) into the flow-cell.