ABSTRACT
Cell fluids are rich in complexing agents which compete for small amounts of metal ions, so that it may be difficult to extrapolate from test tube chemistry and biology to in vivo conditions. One aspect which has been little explored is the contribution that might be made by metal ions and chelating agents in this context. The major part of the transition metal ions is bound to proteins. Although, among first-row transition metal ions, copper complexes are almost always the most stable, it does not follow that the addition of a strong ligand to a multimetal-multiligand system will favor complex formation with copper. Quantitative considerations such as these can provide a useful guide to the possibilities of chelation therapy and to an understanding of the roles of metal ions and chelating agents in biological systems. Many other antiviral compounds, in particular the nucleoside analogs, bind metal ions in pure solutions.
