GC-AED Session: Is That Garlic on Your Breath?

March 14, 2006

E-Separation Solutions

At a session entitled "Atomic Emission Detection for Gas Chromatography," several speakers discussed applications of coupling gas chromatography and atomic emission detection (GC-AED).

An organized contributed session entitled "Atomic Emission Detection for Gas Chromatography" was held on Tuesday afternoon at Pittcon 2006. The session featured several prominent speakers on the applications of coupling gas chromatography-atomic emission detection (GC-AED). Peter Uden of the University of Massachusetts and Marion Hoch of the University of Erlangen-Nurnburg were among the speakers in the session.

The session began with Uden who developed the GC-AED technique during the 1970s. "It's exciting to be here. I don't do conferences anymore," said Uden.

He spoke at length about selenium, which is a part of our diets. Selenium has a narrow window of intake. The average American intakes approximately 80-g daily, which Uden says is satisfactory. "A deficiency is bad," said Uden. He explained that Europeans recently have been experiencing such a deficiency. But too much is not good either. The toxic effects of Selenium include hair loss, nail problems, tooth decay, selenosis, swelling of the fingers and garlic breath.

Next Uden explained that selenium might have a role in cancer prevention as exemplified by the Clark Trial of 1996. Trial subjects who took a daily supplement of selenium saw a 39% reduction in carcinoma incidents and a 48% reduction in mortality.

GC-AED has proven valuable for Uden in speciation and quantitation of such different classes of selenium compounds as selenoanions, selenocations, sigma-bonded neutral organoselenium compounds, aromatic organoseleniums, and selenoamino acids. When analytes are involatile, chemical derivatization methods provide access to volatile derivatives.

Also, GC-AED can determine whether elemental response is independent of molecular structure. This permits compound independent calibration to be used for quantitative determinations.

Then Uden said that organoselenium compounds in exhaled breath of subjects taking selenium supplements can be quantified on capillary columns. This technique potentially could be an excellent monitoring tool of trial subjects in anti-cancer therapy studies.

"Selenium breath, garlic breath. There are reasons why they smell the way they do," concluded Uden.

Later in the session, Hoch spoke about the use of GC-AED for the selective determination and speciation of organotin compounds for geologic applications. Hoch continued to explain organotins such as tributyltin (TBT) are found in products such as wood preservatives and antifouling paints. TBT is extremely toxic and can easily enter aquatic systems through waste water and industrial waste. When in this environment, TBT can be fatal to snails, mussels, and larva stages of some fish.

Hoch explained that GC-AED is "very suitable" for organotin determination and explained her technique. She explained that this research is necessary "to develop applicable decontamination concept and estimate ecological risk."

Terry Ramus of Diablo Analytical (Concord, Massachusetts) arranged and presided the session. The session featured other speakers including Katja Ziegenhals and Joachim Gerstel representing Joint Analytical Systems (Moers, Germany), Darcy Krager of OMIC (Portland, Oregon), Scott J. Hein of Diablo Analytical, Yevgenia Briker of the National Centre for Upgrading Technology (Alberta, Canada), and Paul Adams of UOP (Des Plaines, Illinois).