Cold vapor ionic liquid-assisted headspace single-drop microextraction: a novel preconcentration technique for mercury species determination in complex matrix samples

MARTINIS, E.M.; ALTAMIRANO, J.C.; OLSINA, R.A.; WUILLOUD, R.G.

Mar del Plata

Congreso; ELEVENTH RIO SYMPOSIUM ON ATOMIC SPECTROMETRIC; 2010

Single-drop microextraction (SDME) technique has been widely used in the last years as powerful tool for the preconcentration and matrix separation of a variety of organic and inorganic compounds. However, the use of traditional organic solvent for SDME has the adverse consequences of prolonged extraction time and fast stirring rate of sample solutions might result in drop dissolution or evaporation. Consequently, and to overwhelm these drawbacks, novel solvents are currently under study. Ionic liquids (ILs) have been recently investigated as alternative solvents for SDME technique. ILs have lower emission of volatile organic compounds to the atmosphere among other advantages. In this work, a detailed analytical study on Hg atomic vapor capture by an IL has been developed. Phosphonium-containing IL, tetradecyl(trihexyl)phosphonium chloride CYPHOSÒ IL 101, is proposed for the first time in combination with head space-SDME technique for the separation, preconcentration, and determination of Hg species. The metal vapor was captured into a CYPHOSÒ IL 101 microdrop followed by direct injection into ETAAS for elemental detection. Stannous chloride (SnCl2) was used to reduce Hg2+ to volatile Hg°, while oxidation of OrHg species permitted the determination of total Hg. Mercury was determined in different complex matrix samples like sea water, sea food hair and wine. This microextraction technique is a simple, inexpensive, effective and virtually solvent-free sample pretreatment.   References   S. Risticevic, V. H. Niri, D. Vuckovic and J. Pawliszyn, Anal. Bioanal. Chem., 2009, 393, 781-795. L. Ji, S. W. Thiel and N. G. Pinto, Ind. Eng. Chem. Res., 2008, 47, 8396-8400. S. Gil, S. Fragueiro, I. Lavilla and C. Bendicho, Spectrochim. Acta Part B, 2005, 60, 145-150.