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Protonation effect on drug affinity.

Robert B Raffa·Gregory W Stagliano·Shawn D Spencer
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Abstract

Pharmacologic ligand-macromolecule interactions are commonly characterized by affinity (dissociation) constants such as K(d) or K(i) without regard to the protonation effect of the buffer used in the measurement. The protonation effect is demonstrated here using isothermal titration microcalorimetry measurements of the competitive inhibitor binding of cytidine 2'-monophosphate (2'-CMP) to RNase-A as a model system in buffers of different ionization Delta H(buffer). The results demonstrate the importance of protonation in measures of affinity.

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BuffersCalorimetryCalorimetry, Differential ScanningKineticsLigandsPharmaceutical PreparationsProtonsThermodynamicsJournal Article

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Robert B Raffa, Gregory W Stagliano, Shawn D Spencer. 2004-01-12. Protonation effect on drug affinity.. https://doi.org/10.1016/j.ejphar.2003.10.019

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