Food Safety Magazine

Solutions On Demand | August/September 2013

Ion Chromatography Enhances Workflows

By Thermo

Ion Chromatography Enhances Workflows

Ion Chromatography (IC) has been used successfully for more than 30 years to separate, isolate and identify the components of chemical mixtures, including complex food matrices. Today, some of the most exciting uses of IC involve its coupling with detection techniques such as mass spectrometry (MS) and inductively coupled plasma MS (ICP-MS). Thermo Fisher Scientific has been building on the unique capabilities created by pairing these technologies to develop complete workflow solutions for food contamination analysis.

Perchlorate in Liquid and Powdered Baby Formula
High amounts of perchlorate in liquid and powdered baby formula can trigger adverse health effects in infants by inhibiting iodide uptake by the thyroid gland. The reduced uptake of iodide inhibits thyroid hormone production, which is essential for proper protein expression, neuronal differentiation and other functions. Analytical methods for perchlorate quantification include IC-MS/MS detection. To highlight how the high sensitivity and selectivity of MS detection provides greater data confidence while minimizing labor-intensive sample preparation, an analytical method for ultratrace-level perchlorate analysis was undertaken using the Thermo Scientific™ Dionex™ ICS-3000 Reagent-Free™ IC (RFIC™) system and Thermo Scientific™ TSQ Quantum Access MAX™ Triple-Stage Quadrupole LC-MS. This method demonstrated excellent instrument precision and accuracy, as well as good recovery and reproducibility.
 
Arsenic Speciation In Fruit Juices
Elemental speciation analysis is growing in popularity as producers recognize the need to determine levels of harmful elemental contaminant species versus total contaminant levels. While inorganic forms of arsenic—As(III) and As(V)—are highly toxic, the organic forms (e. g. arsenobetaine) are not considered to be toxic. To demonstrate the abilities of coupling IC with ICP-MS for speciation analysis, apple juice samples were analyzed to determine the concentration of six arsenic species: two inorganic and toxic species—As (III) and As (V)—and four organic species—arsenobetaine (AsB), arsenocholine (AsC), monomethylarsonic acid (MMA) and dimethylarsinic acid (DMA). Chromatographic separations were carried out using the Thermo Scientific Dionex ICS-5000 Ion Chromatography system. The Thermo Scientific™ iCAP™ Qc ICP-MS was then used as a highly sensitive and selective arsenic detector (IC-ICP/MS). The developed method offers high sample throughput that is crucial in food applications where large numbers of samples may have to be rapidly analyzed.

To download Determination of Ultratrace Level Perchlorate in Liquid and Powdered Baby Formula and IC-ICP-MS Speciation Analysis of As in Apple Juice, please visit www.thermoscientific.com/foodsafetyinsider.