In this paper the capillary cold trap (CCT) is presented as a novel sample introduction and separation system for microwave-induced plasma detection. The method is based on cryogenic trapping and gas chromatographic separation carried out within the same capillary. The device, which comprises a derivatization step, on-line gas phase extraction, preconcentration and analyte separation, is semi-automated and all operational parameters are adjustable via an in-house developed control unit, regulating the selected parameters throughout the analysis process. Detection was carried out using a 2.45 GHz microwave-induced argon discharge sustained in a TM010 Beenakker cavity and emission lines were recorded by means of a ST6-UV CCD camera provided by the Santa Barbara Instrument Group. The detection limits achieved were 6.0, 0.95 and 1.25 ng L21 for dimethylmercury, methylmercury and inorganic mercury, respectively. A complete chromatogram could be obtained within 3 min, resulting in the duration of one whole analysis cycle of about 15 min. The proposed method was validated by the analysis of a reference material (BCR 710) and applied to mercury speciation in different sample matrices such as oyster, tuna fish and sediments after microwave-assisted extraction. The total mercury concentration in real samples was in the range of 0.2–11 mg kg21, of which up to 75% corresponded to organic mercury species.

Item Type:	Refereed Article
Keywords:	microwave induced plasma, cold trap, mercury speciation
Research Division:	Chemical Sciences
Research Group:	Analytical Chemistry
Research Field:	Instrumental Methods (excl. Immunological and Bioassay Methods)
Objective Division:	Environment
Objective Group:	Natural Hazards
Objective Field:	Natural Hazards in Mining Environments
Author:	Dietz, C (Dr Christian Dietz)
ID Code:	84814
Year Published:	2001
Web of Science® Times Cited:	25
Deposited By:	Central Science Laboratory
Deposited On:	2013-06-03
Last Modified:	2017-06-06
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