The adsorption of strychnine at a mercury—solution interface

Abstract The adsorption of strychnine in an aqueous acetate buffer has been studied in order to explain the optimum conditions of an electrochemical asymmetric synthesis in which it is used as inductor. In dilute solutions ( m −4 ) the adsorption is a slow kinetic process while at more concentrated values ( m > 10 −4 ) it is affected by an association in solution. This explains the fact that the optimum conditions for the synthesis are known to correspond to a concentration 10 −4 M in strychnine. Further more while it is not adsorbed at very positive charges, this molecule saturates the surface of the electrode for negative charges between −2 and −7 μCcm −2 ie between −500 and −900 mV (Calomel electrode KCl 0.1 M). At still more negative charges (−1300 mV) hydrogen is catalytically discharged.