Ultratrace determination

Since the concentrations of the various compounds or oxidation states in which trace elements can occur are always lower than the total content of the analyte, speciation analysis is normally an ultratrace determination in the ng L-1 range for solutions and the ng g 1 range for... 

Finally, when ultratrace determinations are being performed it is often necessary to preconcentrate the sample or separate the analyte of interest from the matrix. The most commonly employed methods for preconcentration and separation of water samples include evaporation, chelation, coprecipitation, extraction, ion-exchange, chromatography, and electrochemistry. The procedure adopted will depend on the analyte, the form in which it exists, and the sample matrix. 

Kumar K., A. Thompson, A.K. Singh, Y. Chandler, and S.C. Gupta (2004). Enzyme-linked immunosorbent assay for ultratrace determination of antibiotics in aqueous samples. Journal of Environmental Quality 33 250-256. 

Adams, J., E. L. Atlas, and C.-S. Glam, Ultratrace Determination of Vapor-Phase Nitrogen Heterocyclic Bases in Ambient Air, Anal. Chem., 54, 1515-1518 (1982). 

For some applications, precipitation and co-precipitation, which is often incomplete, is utilized. As an example, for trace matrix separation the procedure for plutonium determination by ICP-SFMS in urine after trace matrix separation is summarized in Figure 6.29.86 87 The limit of detection for 239 Pu ultratrace determination in one litre of urine based on enrichment factor of 100 using the DIHEN in ICP-SFMS was 1.02- 10 18g mF1.86... 

Metallic biomaterials (metals such as Ti or its alloys and others) are used for the manufacture of orthopaedic implants due to their excellent biocompatibility with respect to electrical and thermal conductivity and their mechanical properties, e.g., for hard tissue replacement such as total hip and knee joints, for fracture healing aids such as bone plates and screws or dental implants. For example, Co-Cr-Mo alloys are employed for metal-on-metal hip bearings in total joint replacements. Problems with implants occur because of ion release in patients with metal implants. To control this ion release, the ultratrace determination of Co, Cr and Mo in the blood (or serum) and urine of patients with Co-Cr-Mo alloy hip implants is carried out routinely in the author s laboratory. The trace metal determination of Co, Cr and Mo in complex matrices such as urine and blood by ICP-MS is not trivial due to the low concentrations expected in the sub-ngmF1 range, the possible danger of contamination during sample collection, sample preparation and the... 

Different applications of mass spectrometry in the trace and ultratrace determination of long lived radionuclides in nuclear fuel, solid radioactive waste samples, radioactive solutions and... 

Aga, D.S. and E.M. Thurman (1993). Coupling solid-phase extraction and enzyme-linked immunosorbent assay for ultratrace determination of herbicides in pristine water. Anal. Chem., 65 2894-2898. 

Di Corcia, A., C. Crescenzi, E. Guerriero, and R. Samperi (1997). Ultratrace determination of atrazine and its six major degradation products in water by solid-phase extraction and liquid chromatography-electrospray/mass spectrometry. Environ. Sci. Technol., 31 1658-1663. 

Bagheri, H. and A. Salemi. 2004. Coupling of a concentric in-two-tube solid phase microextraction technique with HPLC-fluorescence detection for the ultratrace determination of polycyclic hydrocarbons in water samples. Chromatographia 59 501-505. 

Chang RR, Jarman WM, Hennings JA. 1993. Sample cleanup by solid phase extraction for the ultratrace determination of polychlorinated dibenzo-p-dioxins and dibenzofurans in biological samples. Anal Chem 65 (18) 2420-2427. 

Taylor, M. L., Arnold, E. I. Ultratrace determination of metals in biological spec-imens-quantitative determination of beryllium by gas-chromatography. Anal. 

Greenberg RR, Zeisler R. 1988. A radiochemical procedure for ultratrace determination of chromium in biological materials. J Radioanaly Nucl Chem 124(l) 5-20. 

C. Fragniere, M. Haldimann, A. Eastgate, U. Krahenbuhl, A direct ultratrace determination of platinum in environmental food and biological samples by ICP-SFMS using a desolvation system,. /. Anal. Atom. Spectrom., 20 (2005), 626 D630. 

The new, commercially available heated graphite ETA devices are available at much lower cost than XRF devices, and will certainly encourage expansion of the application of low total mass collection type studies. These heated graphite rods or furnaces are the type of ETA devices which one is most likely to encounter in general air pollution applications and most of this chapter s comments will be directed toward them however, the comments will also be pertinent to special purpose devices such as heated foil and wire atomizers. The reader is directed to Chapters 2 and 3 and to Siemer [9] for general descriptions of ETA devices, their applications, their characteristics and their limitations. Bancroft [10] has reviewed ETA applications to the ultratrace determination of metals. 

Leon, C., Emons, H., Ostapczuk, P., Hoppstock, K. Simultaneous ultratrace determination of platinum and rhodium by cathodic stripping voltammetry. Anal. Chim. Acta 356, 99-104 (1997)... 

Both GC and LC behavior of metal complexes of various ligand types including salicy-laldimines and Schiff bases and fluorinated /3-diketones was reported. Metal ions included the lanthanides, transition metals, Pt, Pd and Zn. Dissociation and thermal instabilities were found to be the main limitations in the chromatography of such derivatives. The data indicate that pre-column derivatization and GC is unlikely to provide a viable method for the ultratrace determination of metal ions except in rare circumstances. On the other hand, LC of complexed metal ions was found as a valuable technique that combines the advantages of versatility, specificity and sensitivity with the capacity for simultaneous determination and speciation. Diastereoisomers of oxovanadium(IV) complexes of tetradentate Schiff bases could be resolved by both GC and LC . ... 

The analysis of PAHs by fluorescence detection HPLC is often the water analysts first introduction to HPLC. The analysis of the WHO six PAHs (section 11.8.1.1) namely fluoranthene, benzo[6]fluoranthene, henzo[k]fluoranthene, benzo[a]pyrene, benzo[g/j/ perylene and indeno[l,2,3-cd]pyrene was carried out using fixed excitation and emission E wavelengths. With the advent of relatively cheap variable wavelength programmable fluorescence detectors, the detectors can be optimised for each separate PAH with a resultant lowering of detection limit. Ultratrace determination of PAHs down to 180fg of benzo[a]pyrene was reported as early as 1983. 

The latest study has revealed that CCC has a great potential in the ultratrace determination of metals, because it can concentrate minute amounts of metal prior to the instrumental multielement analysis, such as atomic absorption spectrometry (AAS), inductively coupled plasma-atomic emission spectrometry (ICP-AES), and inductively coupled plasma-mass spectrometry (ICP-MS). 

G. Scarponi, C. Barbante, P. Cescon, Differential pulse anodic stripping voltammetry for ultratrace determination of cadmium and lead in Antarctic snow, Analusis Magazine, 22 (1994), M47-M50. 

M. A. Bolshov, C. F. Boutron, F. M. Ducroz, U. Gorlach, O. M. Kompanetz, S. M. Rudniev, B, Hutch, Direct ultratrace determination of cadmium in Antarctic and Greenland snow and ice by laser atomic fluorescence spectrometry. Anal. Chim. Acta, 251 (1991), 169-175. 

M. A. Bolshov, S. N. Rudniev, J. P. Candelone, C. F. Boutron, S. Hong, Ultratrace determination of Bi in Greenland snow by laser atomic fluorescence spectrometry, Spectrochim. Acta, 49B (1994), 1445-1452. 

Trace and ultratrace determinations are now very important for chemicals. For solid chemicals dissolution again may put limitations on the power of detection achievable due to contamination during the dissolution procedure. Graphite furnace atomic absorption together with plasma mass spectrometry are now of great importance for the analyzing acids used e.g. in the treatment of surfaces in microelectronic components. 

Sabik, H., Fouquet, A., and Proulx, S., Ultratrace determination of organophosphorus and organonitrogen pesticides in surface water, Analusis, 25, 267-273, 1997. 

More recently for ultratrace determination and speciation of antimony compounds the so-called hyphenated instrumental techniques have been applied which combine adequate separation devices with suitable element-specific detectors. They include high-performance liquid chromatography (HPLC) connected on-line with heated graphite furnace (HGF) AAS (HPLC-HGF-AAS), hydride-generation atomic fluorescence spectrometry (HPLC-HG-AFS) or inductively coupled plasma (ICP) mass spectrometry (MS) (HPLC-ICP-MS) capillary electrophoresis (CE) connected to inductively coupled plasma mass spectrometry (CE-ICP-MS) and gas chromatography (GC) coupled with the same detectors as with HPLC. Reliable speciation of antimony compounds is still hampered by such problems as extractability of the element, preservation of its species information, and availability of Sb standard compounds (Nash et al. 2000, Krachler etal. 2001). Variants of anodic stripping voltammetry for speciation of antimony have also been applied (Quentel and Eilella 2002). 

Simultaneous ultratrace determination of platinum and rhodium by cathodic stripping voltammetry. Anal Chim Acta 356 99—104. 

Stoeppler, M. (1983) Atomic absorption spectrometry -Avaluable tool for trace and ultratrace determinations of metals and metalloids in biological materials. Spectrochim. Acta, 38B, 1559-1568. 

FIGURE IA2-1 Cold-vapor atomic fluorescence system for ultratrace determinations ol mercury. 

A method developed in this laboratory for determining tellurium (36) in brasses and cast irons has been also applicable to ultratrace determinations in almost any matrix. The sensitivity in the final solution (1.5M phosphoric acid) by using the subtractive mode of operation of the cathode-ray polarograph is several p.p.b. 

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