Metallic in biological samples

Angerer J, Schaller KH. 1988. Digestion procedures for the determination of metals in biological samples. In Analysis of hazardous substances in biological materials. Vol. 2. Weinheim, FRG VCH, 1-30. 

Extraction of Pb from iodide solutions into MIBK followed by the determination with dibromo-p-methyl-methylsulfonazo (X - 642 nm e = 1.02 lO"" 1 mof cm ) makes a basis of the determination of the metal in biological samples [1]. The application of meio-tetrakis-(3,5-dibromo-4-hydroxyphenyl)porphyrin (in the presence of 8-hydroxyquinoline and Triton X-lOO) to the determination of lead in clinical samples has recently been described [2]. The detection limit of 0.21 ng ml has been achieved. 

A number of methods have been described for determining the concentrations of toxic metals in biological samples.These methods include graphite furnace atomic absorption spectrometry (GF-AAS), electroanalytical techniques such as anodic stripping voltammetry (ASV), neutron activation analysis (NAA), and mass spectrometry (MS). Amongst these techniques, mass spectrometry occupies a unique role due to its potential to measure the... 

This chapter presents the results of studies carried out for the determination of Pb, Cd, Hg and As using GC-MS. Since GC-MS requires a volatile form of the metal, suitable chelating agents were identified, prepared, and examined for the cross-over (memory) effect. Also the validation of isotope dilution GC-MS for the determination of these toxic metals in biological samples was carried out using suitable NIST certified reference materials. 

One of the main requirements of using GC-MS for the determination of metals is the preparation of a suitable metal chelate, which should have adequate thermal stability and should also be volatile. Further, the metal chelate should not introduce any memory effect or carry-over effect when injecting sequential samples of different isotopic compositions. We have been able to identify suitable metal chelates for the toxic metals Pb, Hg, Cd and As. Another requirement for the determination of toxic metals in biological samples is the development of a suitable digestion procedure, without introducing any contaminants from the reagents employed. 

Results of concentration determination of toxic metals in biological samples... 

Solids or solutions analysis of metals in biological samples possible. 

Determination and Location of Platinum Metals in Biological Samples by Neutron Activation and Microprobe Analyses... 

Fishbein L (1987) Perspectives of carcinogenic and mutagenic metals in biological samples. Int J Environ Anal Chem 28 21-69. 

The following section describes selected studies, representing the potential of voltammetry for determining trace metals in biological samples. 

The molecular mass of ligands associated with metals in biological samples can range from below one hundred to over a million. Consequently, it is not possible to use one gel type to fractionate the various constituents. Hence, before any separation is undertaken the molecular mass range to be investigated should be defined. This would help not only in the choice of the gel type but also in the selection of the method for ligand detection. 

The levels of transition metals in biological samples such as blood serum are frequently important. Many determinations have been made of the levels of (for example) chromium in serum - with startling results. Different workers, all studying pooled serum samples from healthy subjects, have obtained chromium... 

Metals in biological samples are most commonly determined by... 

Huang, C.-C.,Yang, M.-H., and Shih,T.-S. (1997). Automated on-hne sample pretieatment system for the determination of trace metals in biological samples by inductively coupled plasma mass spectrometry. Anal. Chem. 69(19), 3930. 

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