Separation and identification of organic acids in root exudates of Lupinus luteus by capillary zone electrophoresis

The separation and identification of a mixture of organic acids by capillary electrophoresis, with direct detection by UV absorption at a wavelength of 200 nm is reported. A solution containing the following organic acids was studied: oxalic, formic, fumaric, malic, succinic, citric, acetic and lactic acid. Separation was achieved using a fused-silica capillary filled with phosphate buffer (200 mM; pH 6) containing N-acetyl-N,N,N-trimethylammonium bromide (0.5 mM) as cationic surfactant, necessary to modify the electrosmotic dow, The composition of organic acids in exudates of Lupinas luteus was determined by this method. Copyright (C) 1999 John Whey & Sons, Ltd.