Cold vapour generation

ICP-SFMS (Thermo Finnigan, Flement) with cold vapour generation was developed with a guard electrode and a gold amalgamation device using an Au-sorbent for sample pre-concentration to improve the sensitivity. Instrumental parameters of ICP-SFMS such as take-up time, heating temperature of Au-sorbent, additional gas flow, and sample gas flow were optimized. Detection limit calculated as 3 times the standard deviation of 10 blanks was 0,05 ng/1, RSD = 7-9 %. 

Atomic absorption coupled to cold vapour generation. 

Atomic absorption following trapping on gold from cold vapour generation. 

Typical cold vapour generation AAS system used for mercury determination. The same system can be used with a flame in place of the Pyrex tube to allow the determination of hydride -forming elements. 

Clough and co-workers reported on the uncertainty contribution using single and double isotopi-cally enriched spikes in the isotope dilution approach employing a multiple ion collector ICP-MS combined with an HPLC and with cold vapour generation (CV) to form HPLC-CV-MC-ICP-MS for the determination of MeHg in fish tissue.8 Two fish tissue reference materials DORM-2 (NRC, Canada) and BCR 464 were employed in these studies. The amount of each certified reference... 

Gaseous and volatilised analytes can also be easily determined by FAAS and ETAAS. For example, the determination of several elements by the formation of covalent volatile hydrides e.g. arsenic, selenium) and cold vapour generation (mercury and cadmium) is feasible with good analytical sensitivity (see Section 1.4.1.1). 

Krull, I.S., Bushee, D.S., Schleicher, R.G. and Smith, S.B. (1985) Determination of inorganic and organomercury compounds by high performance liquid chromatography-inductive ly coupled plasma emission spectrometry with cold vapour generation. Analyst, 111, 345-349. 

Chiba et al. [749] used atmospheric pressure helium microwave induced plasma emission spectrometry with the cold vapour generation technique combined with gas chromatography for the determination of methylmercuiy chloride, ethylmercury chloride and dimethylmercury in sea water following a 500-fold preconcentration using a benzene- cysteine extraction technique. 

G. Tao, S. N. Willie, R. E. Sturgeon, Determination of total mercury in biological tissues by Bow injection cold vapour generation atomic absorption spectrometry following tetramethylammonium hydroxide digestion, Analyst, 123 (1998), 1215D1218. 

F. Ubillus, A. Algeria, R. Barbera, R. Farre, M. J. Lagarda, Methylmercury and inorganic mercury determination in fish by cold vapour generation atomic absorption spectrometry, Food Chem., 71 (2000), 529-533. 

Cold vapour generation is the term exclusively reserved for mercury. Mercury in a sample is reduced to elemental mercury by tin (II) chloride (eqn 27.2) ... 

Because the hydride and cold vapour generation techniques have so far been used mainly with liquid and dissolved samples, all aspects related to the variables influencing the process and the characteristics of the ensuing methods, among others, have been established in the light of a liquid entering the separator. Most such aspects also affect solid samples and are thus worth some comment, as are those that are exclusive to them — all briefly as this technique has scarcely been applied to solid samples. 

Steady-state and kinetic methods of hydride and cold vapour generation... 

PERFORMANCE AND CHARACTERISTIC DATA OF REPRESENTATIVE FI HYDRIDE AND COLD VAPOUR GENERATION ATOMIC DETECTION METHODS... 

Lee SH, Jung KH, Lee DH. 1989. Determination of mercury in environmental samples by cold-vapour generation and atomic-absorption spectrometry with a gold-coated graphite furnace. Talanta 36(10) 999-1003. 

Liquid samples gasouse extraction (Hydride/cold vapour generation system)... 

Hutton, R.C. and Preston, B. (1980) A simple non-dispersive atomic-fluorescence spectrometer for mercury determination, using cold-vapour generation. Analyst, 105, 981-984. 

AAS determinations based on hydride and cold vapour generation, electrothermal atomization with graphite furnaces have also been used successfully with FI systems to improve the overall performance of these techniques. Special requirements on the atomization-detection systems for hydride and cold vapour generation will be discussed in Chapter 5, and for the graphite furnace, in Chapter 4. 

Experimental designs were used to evaluate the effects of several parameters influencing the cold vapour generation. Relevant variables were optimised with a central composite design. 

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