A novel model to characterize the electric double layer of lectins from Cratylia mollis (Camaratu bean) and Canavalia ensiformis adsorbed on metallic surface

The seed lectin from Cratylia mollis (Cra) is glucose/mannose specific, similarly to Concanavalin A, Con A, a well characterized lectin from Canavalia ensiformis. The equilibrium properties of an adsorbed layer may be examined based on the redox potentials of the constituents of this layer. The potential for Con A and Cra was obtained by potentiostatic techniques, using a saline solution as support to control the distribution of charges between saturated calomel electrode and platinum electrode as the working electrode, in aerated environment. These potentials are modelled using a Chi-square statistical distribution (p < 0.05); greater stability for Con A was obtained with 1.0 mg/ml, at 10 degreesC. The positive redox potential determined for Cra (+94 mV) and Con A (+88 mV) indicated a high sensitivity of our electrodes which will give information on the kinetic behaviour of the biological interface. (C) 2001 Elsevier Science Ltd. All rights reserved.