Avtor/Urednik		Goessler, Walter; Kuehnelt, Doris; Schlagenhaufen, Claudia; Šlejkovec, Zdenka; Irgolič, Kurt J
Naslov		Arsenobetaine and other arsenic compounds in the National research council of Canada certified reference materials DORM 1 and DORM 2
Tip		članek
Vir		J Anal Atom Spectrom
Vol. in št.		Letnik 13
Leto izdaje		1998
Obseg		str. 183-7
Jezik		eng
Abstrakt		A silica-based cation-exchange column was used to determine the arsenic compounds in the National Research Council of Canada (NRCC) CRMs DORM 1 and DORM 2 (Dogfish Muscle). With a 20 mM aqueous pyridine mobile phase at pH 3.0, the concentration of arsenobetaine was only 10.7 mg kg-1 As in the extract of DORM 1. When the same extract was chromatographed on an anion-exchange column, 15.9±0.3 mg kg-1 As (arsenobetaine) were found. The calibration for arsenobetaine was Gnear from 0.5 pg dm-1 As to 10 mg dm-3 As. When the extracts were diluted with water the cation-exchange results approached the anion-exchange results. The multi-element capabilities of ICP-MS allowed the simultaneous monitoring of arsenic and alkali metals. Sodium and potassium were found to co-elute with arsenobetaine. Wheo aqueous solutions of arsenobetaine with 250 mg dm-3 Na were chromatographed, the signal obtained for arsenobetaine was only 60% of the signal without sodium in the solution. When the pH of the 20 mM aqueous pyridine mobile phase was lowered, the alkali metals were separated from arsenobetaine and the results obtained from cationexchange chromatography were not significantly different from the anion-exchange results. Because DORM 1 is no longer available, the arsenic compounds in DORM 2 were determined. No significant difference was found for the concentration of arsenobetaine (15.6 ± 0.7 mg kg-1 As for DORM 1; 16.0±0.7 mg kg-1 As for DORM 2). The concentrations of the minor arsenic compounds (dimethylarsinic acid, arsenocholine, the tetramethylarsonium cation and an unknown arsenic compound) in DORM 2 were only half the concentrations in DORM 1.
Deskriptorji		ARSENICALS BETAINE MUSCLES DOGFISH REFERENCE STANDARDS CHROMATOGRAPHY, HIGH PRESSURE LIQUID SPECTRUM ANALYSIS, MASS