Electrochemical Evaluation of Interactions from Cratylia mollis Seed Lectin with Inhibitor Carbohydrate

Aims: To evaluate the charge transference and the electrochemical potential of Cratylia mollis seed
lectin, Cramoll 1,4, adsorbed on Nafion beads after the interaction of glucose ligand.
Study Design: Based on detection of electrochemical currents and potentials of Cramoll 1,4 by
electrochemical techniques.
Place and Duration of Study: Department of Chemistry, Catholic University of Pernambuco,
between April 2014 and November 2015.
Methodology: Cyclic Voltammetry (CV) was performed in an electrochemical cell containing three
electrodes (a calomel electrode, a platinum wire counter electrode and a platinum electrode),
connected to a potentiostat to obtain electrochemical currents related to the charge transference. An
electrochemical cell containing a calomel electrode and a platinum electrode coupled to a multimeter
was used to register the potentials. A saline solution was used as support to control the charge
distribution inside of the cell. Cramoll 1,4-glucose interaction was evaluated in the concentration of
100, 200 and 300 mM of glucose.
Results: CV measurements showed significant charge transference after Cramoll 1,4-glucose
interaction. Cathodic and anodic peaks paired near 100 mV were detected in the range 100-300 mM
glucose, achieving a maximum current response of 1300 μA, approximately. Positive electrochemical
potentials of Cramoll 1,4 adsorbed to Nafion-beads was achieved showing a linear behaviour with the
increase of glucose concentration at 300 mM.
Conclusion: The system is useful for characterization of lectin-carbohydrate interactions and as a
glucose sensor to estimate the activity of lectins. The use of cyclic voltammetry allowed the detection
of a redox potential of 100 mV to Cramoll 1,4/Nafion-beads through the interaction with different
glucose concentrations and constitutes another approach to determine Cramoll 1,4 activity.
Electrochemical potential measurements generate a linear response for glucose concentrations, being
an alternative for glucose sensing. Charge transference of lectins is a great phenomenon to evaluate
lectin-carbohydrate interactions in biological systems.