Accurate Analysis of Chromium in Foodstuffs by Using Inductively Coupled Plasma Mass Spectrometry with a Collision-Reaction Interface

摘要

Food is a common source of chromium (Cr) exposure. However, it is difficult to analyze Cr in complex food matrices by using inductively coupled plasma mass spectrometry (ICP-MS) because the major isotope, 52Cr, is masked by interference generated by the sample matrix and the plasma gas. Among the systems available to minimize interference, the recently developed collision-reaction interface (CRI) has a different structure relative to that of other systems (e.g., collision cell technology, octopole reaction system, and dynamic reaction cell) that were designed as a chamber between the skimmer cone and quadrupole. The CRI system introduces collision or reaction gas directly into the plasma region through a modified hole of skimmer cone. We evaluated the use of an CRI ICP-MS system to minimize polyatomic interference of 52Cr and 53Cr in various foodstuffs. The 52Cr concentrations measured in the standard mode were 2–3 times higher than the certified values. This analytical method based on an ICP-MS system equipped with a CRI of helium gas was effective for Cr analysis in complex food matrices.