The Alkaline Titration of Ovalbumin in the Presence of Copper(II)

Abstract

The alkaline titration of ovalbumin in the presence of copper(II), together with the measurement of absorption spectra at various pH-levels, showed the progressive displacement of protons from the peptide bonds and increasing chelate formation with increasing pH. The possible mechanism of bond formation and nature of the chelate species formed are discussed. The results provide further evidence that a heterogeneous mixture of chelate species is formed between copper(II) and ovalbumin in the biuret reaction.