Author/Editor     Liang, Lian; Bloom, Nicolas S; Horvat, Milena
Title     Simultaneous determination of mercury speciation in biological materials by GC/CVAFS after ethylation and room-temperature precollection
Type     članek
Source     Clin Chem
Vol. and No.     Letnik 40, št. 4
Publication year     1994
Volume     str. 602-7
Language     eng
Abstract     We developed a method for the simultaneous determination of monomethyl mercury (MMHg), inorganic mercury ŠHg(II)Ć, and total mercury (THg) in biological materials. A variety of biological materials can be digested in methanolic KOH solution. The MMHg and Hg(II) present are converted to volatile ethyl derivatives, methylethyl mercury and diethyl mercury, by an aqueous-phase ethylation reaction with sodium tetraethylborate. The ethyl derivatives are precollected onto a trapping column at room temperature, in case of disconnection with the separation/detection system, and then thermally desorbed into a packed isothermal gas chromatography (GC) column. Eluted organo-Hg compounds from the GC column are decomposed into Hg0, and detection is completed by cold vapor atomic fluorescence spectrometry (CVAFS). Pure standard solutions can be used for calibration. The sum of MMHg and Hg(II) obtained by this method equals the THg value obtained by digestion with HNO3 and H2SO4, reduction with SnCl2, and single-stage amalgamation/CVAFS for all biological materials studied. Absolute detection limits are 0.6 pg and 1.3 pg of Hg as MMHg and Hg(II), respectively, corresponding to 0.3 ng and 0.6 ng/g (wet) of sample.
Descriptors     CHROMATOGRAPHY, GAS
MERCURY COMPOUNDS
SPECTROMETRY, FLUORESCENCE
ALCOHOL, METHYL
BODY FLUIDS
BORATES
CHROMATOGRAPHY, GAS
FISHES
HAIR
HYDROGEN-ION CONCENTRATION
HYDROXIDES
METHYLMERCURY COMPOUNDS
MUSCLES
POTASSIUM COMPOUNDS
SENSITIVITY AND SPECIFICITY
SPECTROMETRY, FLUORESCENCE