肾上腺素的薄层光谱电化学研究

Thin-layer Spectroelectrochemical Investigation of Adrenaline

本文用电化学与紫外可见光谱联用技术研究了肾上腺素在不同pH介质中的电化学氧化反应.在强酸性溶液中电极反应产物确认为醌式肾上腺素,而在pH3.5—4.5的介质中,电极反应的初级产物发生后继化学反应,生成肾上腺素红.由单电位阶跃计时吸收法测定了后继反应的动力学,其表观速率常数随介质pH升高而增大,初级氧化产物的脱质子反应可能是一系列后继化学反应中的控制步骤.

The electrochemical oxidation of adrenaline in media of different pH values was investigated by electrochemical and UV-Vis spactro scopic combination technique. It was confirmed that the product of the anodic oxidation of adrenaline in strong acid medium is adrenalinequinone(A) while in pH 3. 5 - 4. 5, (A) takes part in the following chemical reaction producing adrenochrome, The kinetics of the chemical reaction was studied using single-step chronoabsorbmetry. Its observed rate constant increases with increasing of pH. The deproton reaction of (A) may be the rate-determining step in a series of the following reactions.