Microcolumn packed with YPA(4) chelating resin on-line separation/preconcentration combined with graphite furnace atomic absorption spectrometry using Pd as a permanent modifier for the determination of trace mercury in water samples

A new method using a microcolumn packed with YPA₄ chelating resin as solid-phase extractor has been developed for the separation and preconcentration of trace Hg prior to its measurement by GFAAS with Pd as a permanent modifier. Various parameters such as the amount of the modifier, pH, sample flow rate, the concentration and volume of eluent have been studied in order to find the best conditions for the determination of mercury. The detection limit of the method (3σ) for Hg based on an enrichment factor of 100 was 0.2 ng ml⁻¹. A characteristic mass of 114 pg was obtained for mercury using Pd as a permanent modifier. The relative standard deviation was 2.8% at the 10 ng ml⁻¹ level (n = 5). The method has been applied to the determination of trace mercury in environmental water samples and the recoveries for the spiked samples are in the range of 91-105%.