Determination of iron, copper and lead by inductively coupled plasma mass spectrometry in wine

ObjectiveThe determination of metal content of iron， copper and heavy metal element of lead in wine by inductively coupled plasma mass spectrometry （ICP-MS） was established.MethodsThe wine samples were digested by temperature programmed microwave digestion system. Helium gas was used as reaction gas to eliminate molecular ion interference， and the samples were determined by ICP-MS method. The influence of 56Fe and 57Fe isotopes on the determination results in collision mode and non-collision mode were verified. The differences of three pretreatment methods， microwave digestion， dilution and electrothermic digestion were compared.ResultsThe parameters of the instrument were optimized and the detection limits of the three elements were 0.003-0.007 mg/L， precision of the method was 0.8%-5.1% and the recovery was 90.4%-106.0%. It was proved that the iron content in wine can be determined accurately by microwave digestion-56Fe-collision mode or microwave digestion-57Fe-non-collision mode. The direct dilution method can be used to determine elements of lead and copper quickly and accurately. Contents of iron and lead were determined with certified reference material and results were in the specified range.ConclusionThe method has the advantages of high sensitivity， rapid and accurate detection results， and is suitable for the determination of iron， copper and lead in wine.