邻苯三酚自氧化法测定抗氧化活性的方法研究

通过对邻苯三酚自氧化反应体系的光谱吸收、缓冲液pH值和邻苯三酚浓度对自氧化速率的影响进行研究，建立邻苯三酚自氧化-分光光度法最佳应用体系。确定反应体系总体积为3mL，检测波长在319nm时的测定条件为：缓冲液pH值7．3，邻苯三酚浓度60mmol／L，自氧化速率可达0．060△A／min，线性时间4min；检测波长在420nm时的测定条件为：缓冲液pH值7．8，邻苯三酚浓度80mmol／L，自氧化速率可达0．050△A／min、线性时间3min。新方法建立的紫外和可见光两种检测波长体系，可针对样品的吸收光谱特征选择检测波长，避免了样品自身吸收强对测定检测限的影响，测定pH值接近生物体内真实条件，自氧化速率为最佳检测值且线性时间良好。

Measurement of the antioxidant activity by pyrogallol autoxidation

The effects of absorption spectrum, the pH of buffer and pyrogallic acid concentration on the autoxidation velocity of pyrogallol system were investigated, and the optimum system of pyorgallol autoxidation spectrophotometry was established according to the reaction rules.The reaction volume of reaction system was 3ml.The optimal determining condition when the wavelength was 319nm were as follows: pH of buffer 7.3, pyrogallic acid concentration 60mmol/L, oxidation velocity 0.060△A/min and reaction linearity time 4min.The optimal determining condition when the wavelength was 420nm were as follows: pH of buffer 7.8, pyrogallic acid concentration 80mmol/L, oxidation velocity 0.050△A/min and reaction linearity time 3min.The new wavelength systems having ultraviolet and visible light could be used for the pyrogallic acid reaction system, which could choose the wavelength according to the sample absorption spectrum.The method could eliminate the effect of internal absorption on the detection limit and the pH was close to pH of actual condition in organism.In addition, the autoxidation velocity was the optimum measure value and had better reaction linearity time.