用紫外分光光度法和电位滴定法测定几种植物激素的电离常数

Determination of ionization constant of several plant hormones by ultraviolet spectrophotometry and potentiometric titration

分别采用紫外分光光度法和电位滴定法测定了脱落酸、3-吲哚乙酸、赤霉素、水杨酸等几种植物激素的电离常数,对比分析了两种测试方法的原理、测试步骤和数据处理方法.结果表明,采用两种方法测定的四种样品的电离常数与文献报道值一致,且测量结果的重现性较好;这表明紫外分光光度法和电位滴定法可方便地用于测定有机化合物的电离常数.

Ultraviolet spectrophotometric method and potentiometric titration method were sep- arately adopted to determine the ionization constant of several plant hormones including abscisic acid, 3dndole acetic acid, gibberellic acid and salicylic acid. The principle, procedure, and da- ta-process of the two methods were discussed and compared. Results indicate that the ioniza- tion constants of the ~our samples determined by the two methods are in agreement with that reported in literatures, and they have good reproducibilities. This means that both ultraviolet spectrophotometric method and potentiometric titration method can be well adopted to deter- mine the ionization constants of organic compounds.