Lab on valve-multisyringe flow injection system (LOV-MSFIA) for fully automated uranium determination in environmental samples

• Published in: Talanta (Oxford) 2011-06, Vol.84 (5), p.1221-1227
• Main Authors: Avivar, Jessica, Ferrer, Laura, Casas, Montserrat, Cerdà, Víctor
• Format: Article
• Language: English
• Subjects: Analytical chemistry; Applied sciences; Chemistry; Environmental samples; Exact sciences and technology; Global environmental pollution; LOV; LWCC; MSFIA; Pollution; Preconcentration; Spectrometric and optical methods; Uranium
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2010.12.018

The hyphenation of lab-on-valve (LOV) and multisyringe flow analysis (MSFIA), coupled to a long path length liquid waveguide capillary cell (LWCC), allows the spectrophotometric determination of uranium in different types of environmental sample matrices, without any manual pre-treatment, and achieving high selectivity and sensitivity levels. On-line separation and preconcentration of uranium is carried out by means of UTEVA resin. The potential of the LOV-MSFIA makes possible the fully automation of the system by the in-line regeneration of the column. After elution, uranium(VI) is spectrophotometrically detected after reaction with arsenazo-III. The determination of levels of uranium present in environmental samples is required in order to establish an environmental control. Thus, we propose a rapid, cheap and fully automated method to determine uranium(VI) in environmental samples. The limit of detection reached is 1.9ηg of uranium and depending on the preconcentrated volume; it results in ppt levels (10.3ηgL−1). Different water sample matrices (seawater, well water, freshwater, tap water and mineral water) and a phosphogypsum sample (with natural uranium content) were satisfactorily analyzed.