Instrumental Measurements

Abstract

When one makes physical measurements on a bio-inorganic system a very necessary precursor is the defining of the objectives of the experiment. In some instances we are attempting to answer the question whether complexing is occurring between a metal ion and a given ligand in the biological environment. At other times we know that complexing occurs but need to establish the type of complex — spin paired or spin free? how many ligands are attached to the metal ion? what is the stereochemistry of the complexes formed — cis or trans, etc.? Finally, one frequently needs to know the exact concentrations of the complexes present. Thus, the selection of the correct instrumental approach depends very much on the terms of reference of the question being tackled. Naturally, not all of the methods available in vitro for inorganic chemistry researches can be glibly transposed to biology and applied in vivo.