Study on direct electrochemical behaviors and the electroanalytical method of matrine type alkaloids at glassy carbon electrode / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the direct electrochemical behaviors of matrine (MT), oxymatrine (OMT), sophoridine (SR) and oxysophoridine (OSR) at a glassy carbon electrode in a physiological medium, and to determine the contents of commercial MT and SR pharmaceutical products were determined.</p><p><b>METHOD</b>Their electrochemical behaviors and contents in 0.15 mol x L(-1) NaCl aqueous solutions were obtained by cyclic voltammetry (CV) and square wave voltammetry (SWV) methods.</p><p><b>RESULT</b>The electrochemical experimental results show that the two totally irreversible oxidation peaks for both MT and SR were observed, which potential values are 0.81 V and 0.92 V, and the electrode reaction processes were diffusion-controlled. But for both OMT and OSR, they have no oxidation peaks observed in the same condition as well. The linear range of the concentration of MT and SR and the contents in their products were obtained by SWV.</p><p><b>CONCLUSION</b>The research results can be applied in determination of the contents of commercial MT and SR pharmaceutical products.</p>

Study on electrochemical kinetics of matrine and sophoridine in a physiological medium / 中国中药杂志

<p><b>OBJECTIVE</b>To investigate the kinetic processes of direct electrooxidation for both matrine and sophoridine in a physiological medium.</p><p><b>METHOD</b>Their direct electrooxidative behaviors and the parameters of electrochemical kinetics were obtained by cyclic voltammetry (CV), bulk electrolysis with coulometry, chronocoulometry (CC), chronoamperometry (CA).</p><p><b>RESULT AND CONCLUSION</b>The electrochemical experimental results show that the two totally irreversible oxidation peaks in the region of 0.3-1.2 V vs SCE for both MT and SR were observed, and the electrode reactions processes were diffusion-controlled. Their electron transfer number n and electron transfer coefficient alpha were obtained by CV and electrolysis with coulometry. The diffusion coefficient D and rate constant kf were also calculated by CC and CA.</p>