Determination of Calcium and Magnesium in Soils of Samsun-Çarşamba Region by Using Ion-Selective Electrodes

Abstract

In this study, potentiometric PVC-membrane electrodes were developed with calcium (Ca2+) and magnesium (Mg2+)-selective micro-dimensions with commercially purchased ionophore to determine Ca2+ and Mg2+ ion concentrations in the soil. The potentiometric performance characteristics of the prepared Ca2+ and Mg2+-electrodes were determined and the average potential difference of 23.5 and 27.6 mV was observed for each 10 fold change in concentration versus the parent ion solution in the measurements. The electrodes were found to exhibit linear behavior versus the parent ion solution at a concentration range of 10-1-10-5 mol L-1 and to be highly selective to the parent ion besides the alkali and alkaline earth metal ions. Ca2+ and Mg2+ analyzes of soil samples were performed using potentiometric PVC-membrane ion-selective electrodes prepared in the laboratory. The accuracy of the proposed assay was tested using the AAS technique and the results were found to be in agreement with each other. The results show that the potentiometric PVC-membrane electrodes in the developed Ca2+ and Mg2+-selective micro-dimensions can be used routinely in the determination of these ions in soil samples.

Keywords

• Ion-selective PVC-membrane electrode
• potentiometry
• soil
• calcium
• magnesium