On-line pseudo-stationary magnetic solid-phase extraction using magnetic cation exchange microparticles and its application to the determination of strontium

Abstract

An on-line magnetic solid-phase extraction (MSPE) system using a micrometer-sized cation exchanger was developed for strontium determination by microwave plasma atomic emission spectrometry (MP-AES). Micro-magnetic silica-based particles chemically immobilizing diethyl sulfone functional groups were pseudo-stationarily placed inside a knotted tube reaction flow-coil under the influence of an external magnetic field from two sandwiched magnets. In this study, the effect on the analytical impact was investigated using Sr as a model analytical target. The adsorption of Sr was carried out under acidic conditions, and its elution was performed with a nitric acid solution followed by MP-AES detection. The calculated detection limit was 0.59 μg L⁻¹ with a 10-times sensitivity enhancement factor.