Electrochemical Assessment of the Interfacial Response of Unfractionated Bovine Heparin by Post-Processed Chronoamperometry

Abstract Unfractionated bovine heparin (UFH-bov) is a highly sulfated and polydisperse glycosaminoglycan whose interfacial behavior can influence electrochemical mass transport. In this study, chronoamperometric current–time transients obtained for UFH-bov-containing solutions were numerically integrated to generate charge–time profiles and evaluate the concentration-dependent electrochemical response. The corresponding plots of accumulated charge as a function of the square root of time exhibited approximately linear regions within selected analysis intervals. However, UFH-bov is not directly electroactive under the experimental conditions employed and does not undergo a defined stoichiometric electron-transfer reaction. Consequently, the measured charge cannot be quantitatively related to molecular UFH-bov flux through the classical Cottrell–Anson formalism, and the experimental slopes were not converted into molecular diffusion coefficients. Instead, the slope of the selected Qt versus t1/2 region is interpreted only as an operational descriptor of the UFH-bov-dependent electrochemical response. The observed concentration dependence is consistent with interfacial phenomena, including adsorption, partial electrode blocking, and modulation of background electrochemical processes. This revised interpretation provides a conservative framework for describing square-root-of-time-dependent electrochemical behavior in the presence of a non-directly electroactive sulfated polysaccharide without assigning an unsupported molecular diffusion coefficient.