title: Ultrasound-assisted dispersive micro solid-phase extraction with nano-TiO2as adsorbent for the determination of mercury species.
abstract: The combination of ultrasound-assisted dispersive micro solid-phase extraction (USA DMSPE), with the use of TiO2nanoparticles (NPs) as adsorbent, with cold vapor atomic absorption spectrometry (CV AAS) is proposed for preconcentration and determination of mercury species (Hgtotal, Hg2+and CH3Hg+) in biological, geological and water samples. The experimental parameters including the amount of TiO2NPs, pH of sample solution, ultrasonication and centrifugation time, TiO2slurry solution preparation before injection to CV AAS were investigated. Effective preconcentration of trace mercury with 10mg of TiO2was achieved in pH 7.5. After extraction, adsorbent with analytes was mixed with 500μL of 1molL-1HNO3to prepare slurry solution. The concentration limit of detection was 0.004ngmL-1for Hg2+. The achieved preconcentration factor was 35. The relative standard deviations (RSDs, %) for mercury species in real samples were 4-20%. The accuracy of this method was evaluated by analyses of certified reference materials: DOLT-2 (Dogfish Liver), IAEA-085 (Human hair), SRM 2709 (San Joaquin Soil), SRM 2711 (Montana Soil) and SRM 2704 (Buffalo River Sediment). The measured mercury species contents in reference materials were in satisfactory agreement with the added amounts (according to the t-test for a 95% confidence level). The presented method has been successfully applied for the determination of mercury species in real water samples (lake and river water).
authors: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland.
authors: Magdalena
authors: M
authors: Krawczyk
authors: Faculty of Chemical Technology, Poznan University of Technology, Berdychowo 4, 60-965 Poznań, Poland. Electronic address: Ewa.Stanisz@put.poznan.pl.
authors: Ewa
authors: E
authors: Stanisz
keywords: CV AAS; Dispersive micro solid-phase extraction; Mercury speciation; TiO(2); Ultrasound