Laboratory Practice—Possibilities for Mass Spectrometry

Medical laboratory practice—possibilities for mass spectrometry 

Division of Biochemical and Paediatric Genetics, University Children s Hospital, Vienna, Austria 

Analysis of organic acids including orotic acid 

Assessment of in vivo metabolism using stable isotope techniques 

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Medical laboratory practice—possibilities for mass spectrometry... 

Flame atomic absorption was until recently the most widely used techniques for trace metal analysis, reflecting its ease of use and relative freedom from interferences. Although now superceded in many laboratories by inductively coupled plasma atomic emission spectrometry and inductively coupled plasma mass spectrometry, flame atomic absorption spectrometry still is a very valid option for many applications. The sample, usually in solution, is sprayed into the flame following the generation of an aerosol by means of a nebulizer. The theory of atomic absorption spectrometry (AAS) and details of the basic instrumentation required are described in a previous article. This article briefly reviews the nature of the flames employed in AAS, the specific requirements of the instrumentation for use with flame AAS, and the atomization processes that take place within the flame. An overview is given of possible interferences and various modifications that may provide some practical advantage over conventional flame cells. Finally, a number of application notes for common matrices are given. 

Mass spectrometry is a powerful tool in environmental chemistry because of its detection power, specificity, and structure analysis capabilities. Techniques have been developed for the determination of catabolites and metabolites of chemicals in practically all relevant matrices since no other comparable tool is available, even though technical problems can occur. Generally, sample preparation uses at least one type of chromatography. connected with MS either off-line or online. Of the on-line combinations ( hyphenated techniques"), GC/MS is the most successful, even-though LC/MS is rapidly catching up in this area. The development of benchtop GC/MS and LC/MS instruments has made it possible to use mass spectrometry in routine laboratories and even in the field [173]. 

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