Laser microprobe mass analyzer

There are now several different types of machines that are all capable of microanalysis. All have advantages and disadvantages, but the choice of which to use is often governed by expense and availability to a particular institution. Electron probe microanalysis is by far the most popular, but here particle-induced X-ray emission (PIXE), the laser microprobe mass analyzer (LAMMA), electron energy loss spectroscopy (EELS), and secondary ion mass spectrometry (SIMS) are also considered. 

F. Hillenkamp, E. Unsold, R. Kaufmann, and R. Nitsche. A High-Sensitivity Laser Microprobe Mass Analyzer. Appl. Phys., 8(1975) 341-348. 

Optical examination of etched polished surfaces or small particles can often identify compounds or different minerals hy shape, color, optical properties, and the response to various etching attempts. A semi-quantitative elemental analysis can he used for elements with atomic number greater than four by SEM equipped with X-ray fluorescence and various electron detectors. The electron probe microanalyzer and Auer microprobe also provide elemental analysis of small areas. The secondary ion mass spectroscope, laser microprobe mass analyzer, and Raman microprobe analyzer can identify elements, compounds, and molecules. Electron diffraction patterns can be obtained with the TEM to determine which crystalline compounds are present. Ferrography is used for the identification of wear particles in lubricating oils. 

In general, in ICP-MS, metal argide ions (MAr+) are observed at lower intensities compared to the dimeric metal oxide ions (MO+). Both ionic species correlate with the bond dissociation energies in the ICP or by the expansion of plasma in the vacuum. A correlation of measured oxide ion intensities (MO+) and experimentally determined or theoretically calculated bond dissociation energies of oxides has been found in laser mass spectra using a LAMMA 500 (laser microprobe mass analyzer, Leybold Hereaus AG, Cologne) by Michiels and Gijbels.52... 

Laser microprobe mass analyzers permit mass spectrometric analysis of very small volumes (0.01-1 pm3) of thin Sections. The method is based on laser induced ion production from a microvolume and analysis of the evaporated ions in a time-of-flight mass-spectrometer. The technique allows detection of all elements and isotopes with a sensitivity approaching the ppm range and an extremely low limit of detection 10 15 to 10-20 g. Transmission type instruments such as the LAMMA 500 are designed for the analysis of particles of 3 pm in diam. The lateral resolution is about 0.5-1 pm. Because the area to be analyzed is selected by an optical microscope, distribution of chemical constituents can be precisely correlated with morphologic structures (Hillenkamp et al., 1982 39), Simons, 198440), Kaufmann, 1984)41 >. 

Ions Ion Scattering Mass Spectroscopy, Laser Microprobe Mass Analyzer, Rutherford Backscattering Spectroscopy, Secondary Ion Mass Spectroscopy. 

Perl DP, Munoz-Garcia D, Good PF, et al Intracytoplasmic aluminum accumulation in neurofibrillary tangle-bearing neurons detection by laser microprobe mass analyzer (abstract). Ann Neurol 18 143, 1985... 

Schmidt. P.F. (1984). Localization of trace elements with the laser microprobe mass analyzer (LAMMA), Trace Elements in Medicine, 1,13-20 Sherwood. R.A., Rocks, B.F., and Riley, C. (1984). The use of flow-injection analysis (FIA) with atomic absorption detection for the determination of clinically relevant elements. Paper presented at 2nd BNAAS Symposium, Leeds, July 1984 Triebig, G., and Schaller, K.H. (1984). Copper, in Alessio, L, Berlin, A., Boni, M., Roi, R., Biological indicators for the assessment of human exposure to industrial chemicals, p. 57-62, EUR 8903 EN, Commission of the European Communities Van der Vyner, F.L, Verbreuken, A.H., Van Grieken, R.E., and DeBroe, M.E. (1985) Laser microprobe mass analysis A tool for evaluating histochemical staining of trace elements, Clin. Chem., 31. 351... 

Hillenkamp F, Unsoeld E, Kaufman R, Nitsche R. Eligh-sensitivity laser microprobe mass analyzer. Appl Phys 1975 8 341-348. 

Lasers have been used in mass spectrometry for many years. Trace elements in biological samples [90] can be determined by using laser microprobes (LAMMA, laser microprobe mass analyzer) or a combination of laser ablation with ICPMS. For the analysis of bulk materials, techniques such as resonance ionization mass spectrometry (RIMS) and laser ablation MS (LAMS) are employed for a review see [91]. 

Schmidt PF, Barckhaus RH, Kleimeier W (1986) Laser microprobe mass analyzer investigations on the localization of cadmium in renal cortex of rats after longterm exposure to cadmium. Trace Elem Med 3 19-24. 

Guest, W. H. Recent developments of laser microprobe mass analyzers, lamma-500 and lamma-1000. Int. J. Mass Spectrom. Ion Processes 1984, 60, 189-199. 

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