Solvation of small biomolecules

Yet another question is how are small biologically important molecules normally aquated This is important when considering the distribution of such molecules within cells. It is probable that molecules such as Oj or NO are in clathrate-type cages in water. There is some evidence for weak hydrogen bonding for CO2 in water [54], although the normal view is that these molecules are also enclathrated [55]. 

Another potentially important example in which solvation can play a major role is the conversion of oxygen into the superoxide ion, Oj , mentioned in section 3.4.4. If the oxygen is in aqueous solution, aquation of O f will occur in the picosecond time-scale, and the active agent will be fully aquated Oj. However, oxygen is very lipid soluble, and if 0 2 formation occurs in that phase, the ion will remain unsolvated for a relatively long time. Such dry Oj ions are very much more reactive than the solvated ions with respect to their electron-donating power, their free-radical nature, and also their ability to act as nucleophiles [56]. 

These are just a few examples. The field of bio-solvation is surely one of extreme importance, and I am sure that spectroscopic methods will play an important and exciting role in its exploration. 

for example D. Marsh (1985) Spectroscopic Studies of Dynamic Molecular Biological Systems, Academic Press, New York, p. 209. 

Sharp and M.C.R. Symons (1972) in Ions and Ion-Pairs in Solution, ed. M. Schwarc, Wiley, New York. 

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