铝对多巴胺和左旋多巴氧化的化学催化作用的电化学和光谱学研究

Electrochemical and Spectrometric Studies on the Catalytic Effect of Aluminum on the Oxidation of Dopamine and L-Dopa

用电化学、紫外 可见光谱和13C 核磁共振谱研究了铝(Ⅲ)对多巴胺和左旋多巴氧化的化学催化作用。结果表明,在中性和碱性条件下铝(Ⅲ)均能促进多巴胺和左旋多巴的氧化,这一促进作用提高了用多巴胺和左旋多巴作电活性配体示差脉冲伏安法间接测铝的灵敏度。但是抗坏血酸有抑制铝(Ⅲ)的催化效应的作用。

The catalytic effect of aluminum Al(Ⅲ) on the oxidation of both dopamine (DA, 3,4-dihydroxyphenylethylamine) and L-dopa (3,4-dihydroxyphenylalanine) has been studied with electrochemical methods, UV-vis spectroscopy, and^(13)C nuclear magnet resonance. The results indicated that Al(Ⅲ) potentiated the oxidation of these two catecholamines and the higher the values of pH, the more prominent the catalytic effect. This enhanced the sensitivity of the indirect determination of Al(Ⅲ) using DA or L-dopa as an electroactive chelant. However, the oxidation products of both DA and L-dopa in the presence of Al(Ⅲ) were reduced by the addition of ascorbic acid.