Abstract A new method has been developed for the determination of Tl(I) based on simultaneous
sorption and preconcentration with a microcolumn packed with TiO2 nanoparticle with a high specific
surface area prepared by Sonochemical synthesis prior to its determination by graphite furnace
atomic absorption spectrometry (GFAAS). The optimum experimental parameters for preconcentration
of thallium, such as elution condition, pH, and sample volume and flow rate have been
investigated. Tl(I) can be quantitatively retained by TiO2 nanoparticles at pH 9.0, then eluted completely
with 1.0 mol L1 HCl. The adsorption capacity of TiO2 nanoparticles for Tl(I) was found to
be 25 mg g1. Also detection limit, precision (RSD, n= 8) and enrichment factor for Tl(I) were
87 ng L1, 6.4% and 100, respectively. The method has been applied for the determination of trace
amounts of Tl(I) in some environmental water samples with satisfactory results.