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Bioinorganic Chemistry: A Short Course, Second Edition, by Rosette M. Roat-Malone
Copyright © 2007 John Wiley & Sons, Inc.

3 Instrumental Methods

3.1 Introduction,

3.1.1 Analytical Instrument - Based Methods

Lawrence Que, Jr., has stated in the preface to Physical Methods in Bioinor-
ganic Chemistry : “ By piecing together the various clues derived from the
physical methods, bioinorganic chemists have been able to form a coherent
picture of the metal binding site and to deduce the role of the metal ion in a
number of biological processes. ” 1a Physical methods are used for analysis of
systems under study by all chemists, whether or not they are trained analytical
chemists. Therefore all researchers must become familiar with the capabilities
and limitations of the analytical methods they use. In addition to instrumental
and physical methods, chemists have additional investigational capabilities
based on computer methodology. This chapter contains an introduction to
some physical (instrumental), and Chapter 4 will address computer - based
methods. The discussion is not intended as an exhaustive description or even
listing of available methods but rather concentrates on those mentioned fre-
quently in this text. The methods include X - ray absorption spectroscopy (XAS
and EXAFS), X - ray crystallography, nuclear magnetic resonance, electron
paramagnetic resonance (including ENDOR), mass spectrometry, and M ö ss-
bauer spectroscopies. The last method mentioned is especially relevant for
characterization of bioinorganic iron - containing species. Other important
methods used to analyze bioinorganic species such as ultraviolet – visible, infra-