Croatica Chemica Acta
نویسندگان
چکیده
Adsorption effects in square-wave and d. c. polarography of berberine are investigated in the supporting electrolytes of various pH. Tensametric a. c. and SW polarographic measurements show that both berberine and canadine are strongly adsorbed in the potential range between -0.3 V and --'1.7 V vs. SCE. The reduction of berberine proceeds from the adsorbed state and requires four electrons. The coefficients ana = 1.32 and D = (4.0 ± 0.5) . 10-6 cm2/s are evaluated. There are two kind of faradaic SW responses: the first is associated with very low surface coverage while the second appears when the surface is totally covered by the adsorbed berberine. In d. c. polarography a pseudo-prewave and pseudo-main wave appear.·If pH > 6 the limiting currents of d. c. polarographic waves are severely depressed.
منابع مشابه
A Theoretical Information Approach to Ring and Total Aromaticity' in Ground and Excited States
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تاریخ انتشار 2017