Acid-Base Equilibria in Titrations
Due to their ionizable functional groups, all amino acids have a certain buffering capability. Most contain at least a carboxylic acid and an amine group, and others contain additional groups that have the capacity to be protonated or deprotonated. Their buffering ability is due to the fact that, at a certain pH, a functional group will ionize and gain or lose a proton. This pH is characterized by a functional group’s pKa value, which is the point at which fifty percent of the molecules in a sample with that particular group are protonated and fifty percent are deprotonated. Because the pH of a solution is determined by its concentration of free H+, the pH will remain relatively constant around the pKa values due to the rapid uptake or release of protons by the ionizable groups of an amino acid.
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November 21, 2008 @ 2:40 pm
acid-base equilibria rocks
November 21, 2008 @ 2:40 pm
biochem is awesome