Humic acids (HA) are the product of plant and animal decay in soils. These organic substances are of interest because they exhibit metal binding and they bind, release and reduce metal agents. This paper reports a study of the interactions of adenine, adenosine and adenosine-5'-monophosphate with a solid humic acid isolated in our laboratory from Irish peat. In view of the need for iron as a plant nutrient, we loaded the HA with Fe(III) to reduce its solubility and to reveal the effect of Fe(III) on interactions of HA with the adenine triad solutes. The systems were studied at different temperatures from 5.0-35.0^oC to obtain thermodynamic parameters used in mechanism building and modeling.

References

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