肾上腺素的薄层光谱电化学研究

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 p H 介 质中的电化学氧化反应.在强 酸性溶液中电极 反 应产物确认为醒式 肾上 腺素,而 在 p H 3.5 一 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 p H 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.

Thin-layer Spectroelectrochemical Investigation of Adrenaline

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.