Lead, mass spectrometry analytical

Furuta, N. (1991). Interlaboratory comparison study on lead isotope ratios determined by inductively coupled plasma mass spectrometry. Analytical Sciences 7 823-826. 

Walder, A.J. and Furuta, N. (1993). High-precision lead isotope ratio measurements by inductively coupled plasma multiple collector mass spectrometry. Analytical Sciences 9 675-680. 

De Muynck, David, Christophe Cloquet, Elisabeth Smits, Frederik A. de Wolff, Ghylaine Quitte, Luc Moens, and Frank Vanhaecke. Lead Isotopic Analysis of Infant Bone Tissue Dating from the Roman Era Via Multicollector ICP-Mass Spectrometry. Analytical and Bioana-lytical Chemistry 390 (2008) 477-486. The researchers used isotope analysis to show that high concentrations of lead in the bones of Roman infants probably did not come from the soil or other objects in the graves. 

Uryu, T, J. Yoshinaga, Y. Yanagisawa, M. Endo, and J. Takahashi. 2003. Analysis of lead in tooth enamel by laser ablation-inductively coupled plasma-mass spectrometry. Analytical Sciences 19 1413. 

Specifically for triazines in water, multi-residue methods incorporating SPE and LC/MS/MS will soon be available that are capable of measuring numerous parent compounds and all their relevant degradates (including the hydroxytriazines) in one analysis. Continued increases in liquid chromatography/atmospheric pressure ionization tandem mass spectrometry (LC/API-MS/MS) sensitivity will lead to methods requiring no aqueous sample preparation at all, and portions of water samples will be injected directly into the LC column. The use of SPE and GC or LC coupled with MS and MS/MS systems will also be applied routinely to the analysis of more complex sample matrices such as soil and crop and animal tissues. However, the analyte(s) must first be removed from the sample matrix, and additional research is needed to develop more efficient extraction procedures. Increased selectivity during extraction also simplifies the sample purification requirements prior to injection. Certainly, miniaturization of all aspects of the analysis (sample extraction, purification, and instrumentation) will continue, and some of this may involve SEE, subcritical and microwave extraction, sonication, others or even combinations of these techniques for the initial isolation of the analyte(s) from the bulk of the sample matrix. 

The development of a robust analytical method is a complex issue. The residue analyst has available a vast array of techniques to assist in this task, but there are a number of basic rules that should be followed to produce a reliable method. The intention of this article is to provide the analyst with ideas from which a method can be constructed by considering each major component of the analytical method (sample preparation, extraction, sample cleanup, and the determinative step), and to suggest modern techniques that can be used to develop an effective and efficient overall approach. The latter portion emphasizes mass spectrometry (MS) since the current trend for pesticide residue methods is leading to MS becoming the method of choice for simultaneous quantitation and confirmation. This article also serves to update previous publications on similar topics by the authors. ... 

The low concentrations of lead in plasma, relative to red blood cells, has made it extremely difficult to accurately measure plasma lead concentrations in humans, particularly at low PbB concentrations (i.e., less than 20 pg/dL). However, more recent measurements have been achieved with inductively coupled mass spectrometry (ICP-MS), which has a higher analytical sensitivity than earlier atomic absorption spectrometry methods. Using this analytical technique, recent studies have shown that plasma lead concentrations may correlate more strongly with bone lead levels than do PbB concentrations (Cake et al. 1996 Hemandez-Avila et al. 1998). The above studies were conducted in adults, similar studies of children have not been reported. 

Delves HT, Campbell MJ. 1988. Measurements of total lead concentrations and of lead isotope ratios in whole blood by use of inductively coupled plasma source mass spectrometry. J Analytical Atomic Spectrometry 3 343-348. 

However, IHC as a practical method continues to evolve with increasing demands for standardization, and for true quantification of protein analytes by weight, in the context of their cellular microenvironment. Further studies combining proteomics by mass spectrometry and IHC are likely to lead to the refinement of both methods in the analysis of FFPE tissues. The end result may be the creation of a broader field that defines and quantifies protein expression at a cellular level, incorporating the advantages of the wide spectrum of proteins demonstrable by mass spectrometry and the precise localization offered by IHC. 

In soft ionization methods the excess energy deposited onto the ionized molecule is very small and stable even-electron ions are formed. This leads to easy determination of the molecular weight of the analyte, but as fragmentation is absent or it occurs to a very low extent, structural information is missing in the mass spectrum. However, one can obtain structural information by causing ion fragmentation out of the source by means of tandem mass spectrometry experiments (see below). 

The following analytical techniques seem to be adequate for the concentrations under consideration copper and nickel by Freon extraction and FAA cold vapour atomic absorption spectrometry, cobalt by Chelex extraction and differential pulse polarography, mercury by cold vapour atomic absorption absorptiometry, lead by isotope dilution plus clean room manipulation and mass spectrometry. These techniques may be used to detect changes in the above elements for storage tests Cu at 8 nmol/kg, Ni at 5 nmol/kg, Co at 0.5 nmol/kg, Hg at 0.1 nmol/kg, and Pb at 0.7 nmol/kg. 

Barnes, I.L., Murphy, T.J., Gramlich, J.W. and Shields, W.R. (1973). Lead separation by anodic deposition and isotopic ratio mass spectrometry of microgram and smaller quantities. Analytical Chemistry 45 1881-1884. 

Nowadays, ESI is the leading member of the group of atmospheric pressure ionization (API) methods and the method of choice for liquid chromatography-mass spectrometry coupling (LC-MS, Chap. 12). [10-13] Currently, ESI and MALDI (Chap. 10) are the most commonly employed ionization methods and they opened doors to the widespread biological and biomedical application of mass spectrometry. [5,10,11,13-17] Moreover, ESI serves well for the analysis of ionic metal complexes [18,19] and other inorganic analytes. [20-22]... 

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