Determination of iodide in urine using electrospray ionization tandem mass spectrometry

A rapid and sensitive electrospray ionization (ESI) tandem mass spectrometry (MS-MS) procedure was developed for the determination of iodide (I-) A gold (Au) and I- complex was formed Immediately after the addition of the chelating agent NaAuCl4 to I- solution. and was extracted with methyl isobutyl ketone One to five microliters of the extract were injected directly into an ESI-MS-MS instrument I- quantification was performed by selecting reaction monitoring of the product ion I- at m/z 127 derived from the precursor ion (AuI2-)-Au-197 at m/z 451 I- concentration was measured in the quantification range from 10(-7) to 10(-5) M using 50 mu L of solution within 10 min Iodate was reduced to I- with ascorbic acid and determined I- concentration in reference urine 2670a was measured after treatments (C) 2010 Elsevier B V All rights reserved