3D-printed flow manifold based on potentiometric measurements with solid-state ion-selective electrodes and dedicated to multicomponent water analysis.

A 3D-printed flow manifold dedicated to potentiometric simultaneous determination of potassium, sodium, calcium and chloride in water is presented. The method is based on application of miniature solid-contact ion selective electrodes with a special design obtained with the use of 3D printing. The electrodes offer many attractive advantages including short response time and miniaturization feasibility. The use of the proposed novel electrodes enables performance of rapid potentiometric measurements in flow-injection technique and registration of many injection peaks in a short time. One of the advantages of using a special 3D-printed flow vessel for potentiometric measurements was miniaturization of electrodes and the possibility of integrating several (from three up to six) ion selective electrodes in one module enabling realization of multi-component analyses in the same time. Thanks to that the volume of each solution and measurement time were significantly reduced during multi-component analysis. In order to find out if the proposed manifold works properly, three multi-component synthetic samples and four certified reference materials were analyzed. The presented study shows that the proposed 3D-printed flow manifold with solid-state ion-selective electrodes could be an effective tool in a modern multi-component analysis meeting the requirements of green analytical chemistry.