Reusable selective sensing-substrate for ultrasensitive and rapid detection of uranium radioisotopes

Abstract

An analytical method based on a fabricated analytical disc was developed using a phosphonate-immobilized quartz substrate for the rapid analysis of uranium. Phosphonate groups selectively adsorb uranium dissolved in a solution through the formation of stable complexes. The uranium concentration and isotopic ratios in the sample can rapidly be determined by measuring the radioactivity of the adsorbed uranium on the analytical disc using alpha-particle spectrometry. The chemical structure and elemental composition of the fabricated disc were analyzed by XPS, and the adsorption properties were evaluated as functions of pH of a sample solution, reaction time, and adsorbate concentration, as well as reusability and selectivity, using alpha-particle spectrometry, ICPOES, and ICP-MS. An analytical method was developed based on these properties and validated with prepared uranium solutions by assessing the chemical recovery yield, relative error, and relative standard deviation. The developed method is expected to be used for on-the-spot uranium analysis.