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J Chromatogr A

Title:		Another glimpse over the salting-out assisted liquid-liquid extraction in acetonitrile/water mixtures
Author(s):		Valente IM; Goncalves LM; Rodrigues JA;
Address:		"REQUIMTE - Departamento de Quimica e Bioquimica, Faculdade de Ciencias, Universidade do Porto, Rua do Campo Alegre no. 687, 4169-007 Porto, Portugal. inesmariavalente@sapo.pt"
Journal Title:		J Chromatogr A
Year:		2013
Volume:		20130808
Issue:
Page Number:		58 - 62
DOI:		10.1016/j.chroma.2013.08.014
ISSN/ISBN:		1873-3778 (Electronic) 0021-9673 (Linking)
Abstract:		"The use of the salting-out effect in analytical chemistry is very diverse and can be applied to increase the volatility of the analytes in headspace extractions, to cause the precipitation of proteins in biological samples or to improve the recoveries in liquid-liquid extractions. In the latter, the salting-out process can be used to create a phase separation between water-miscible organic solvents and water. Salting-out assisted liquid-liquid extraction (SALLE) is an advantageous sample preparation technique aiming HPLC-UV analysis when developing analytical methodologies. In fact, some new extraction methodologies like QuEChERS include the SALLE concept. This manuscript discusses another point of view over SALLE with particular emphasis over acetonitrile-water mixtures for HPLC-UV analysis; the influence of the salting-out agents, their concentration and the water-acetonitrile volume ratios were the studied parameters. alpha-dicarbonyl compounds and beer were used as test analytes and test samples, respectively. The influence of the studied parameters was characterized by the obtained phase separation volume ratio and the fraction of alpha-dicarbonyls extracted to the acetonitrile phase. Results allowed the distribution of salts within three groups according to the phase separation and their extractability: (1) chlorides and acetates, (2) carbonates and sulfates and (3) magnesium sulfate; of all tested salts, sodium chloride had the highest influence on the alpha-dicarbonyls fraction extracted"
Keywords:		Acetonitriles/*chemistry Carbonates/chemistry Chlorides/chemistry Liquid-Liquid Extraction/*methods Salts/*chemistry Sulfates/chemistry Water/*chemistry Dicarbonyls in beverages Homogeneous liquid-liquid extraction Phase separation Salting-out assisted li;
Notes:		"MedlineValente, Ines Maria Goncalves, Luis Moreira Rodrigues, Jose Antonio eng Research Support, Non-U.S. Gov't Netherlands 2013/08/21 J Chromatogr A. 2013 Sep 20; 1308:58-62. doi: 10.1016/j.chroma.2013.08.014. Epub 2013 Aug 8"