Thermo Fisher Scientific Inc. announced that its Dionex ICS-5000 reagent-free ion chromatography system can be coupled with the Thermo Scientific XSERIES 2 ICP-Q-MS to create a proven IC-ICP-MS method for detecting trace element species, including levels of organic and inorganic arsenic in apple juice.
Background:
A Consumer Reports investigation recently revealed elevated levels of arsenic up to 25 ppb in juice samples. The organization had tested 88 samples of apple juice and grape juice purchased in August and September, 2011, in Connecticut, New Jersey, and New York. While there is no federal limit for arsenic or lead in juice, the tests indicated that 25 percent of samples exceeded the 5-ppb (parts per billion) total lead limit for bottled water, and 10 percent exceeded the 10-ppb limit for total arsenic in drinking water.
The Thermo Scientific hyphenated system:
Photo: IC-ICP-MS system: Dionex ICS-5000 system coupled to XSERIES 2 ICP-Q-MS system
Thermo Fisher’s highly sensitive and selective equipment can distinguish between both inorganic and organic types of arsenic. The distinction is important, as inorganic forms of arsenic are highly toxic whereas organic forms are not. Arsenic is a naturally-occurring element that is sometimes found in drinking water and fruit juices, entering during agricultural and industrial processes. Because typical levels of total arsenic found in apple juice are lower than the U.S. Environmental Protection Agency (EPA) drinking water maximum contaminant level, apple juice is generally considered safe and is currently not regulated.
“Thermo Fisher has developed a highly sensitive and specific method for analyzing arsenic levels in apple juice,” said John W. Plohetski, vice president and general manager, ion chromatography/sample preparation business unit at Thermo Fisher. “The ability to distinguish between organic and inorganic forms of arsenic is critical, and our equipment is sensitive enough to capture that data accurately and reliably.”
To demonstrate the capabilities of the combined Dionex ICS-5000 and Thermo Scientific XSERIES 2 for arsenic speciation analysis, Thermo Fisher tested four apple juice brands purchased from a local supermarket. Using the Dionex IC system for chromatographic separations and the XSERIES 2 mass spectrometer for detection, researchers developed a highly sensitive, routine IC-ICP-MS method for determining trace metal species, including arsenic. The method can be used in the analysis of different juices after a simple 10-fold dilution.
Related Application Notes from Thermo Scientific: #30012: High Sensitivity Arsenic Speciation: HPLC Sector Field ICP-MS #40653: Determination of Organo-Arsenic Species in Seaweed Extracts using HPLC-ICP-MS #40720: Determination of Arsenic Species in Urine Using HPLC Coupled with X Series ICP-MS #40741: Speciation of Arsenic in Fish Tissues using HPLC coupled with X SeriesII ICP-MS