在HAc存在下,少量维生素P4可催化KBrO3氧化丙基红的反应,导致丙基红在521 nm处吸光度显著减小,据此建立了测定维生素P4含量的催化动力学新体系。其线性范围为0.01～0.9 mg/L,检出限为8.9×10-3 mg/L,催化反应总速率常数为9.90×10-4/s。该方法可用于维脑路通片剂和槐米中维生素P4含量的测定。 In the presence of HAc, a small amount of vitamin P4 catalyzed the reaction of KBrO3-propyl red, resulting in a significant decrease of the absorbance of propyl red at 521 nm. A new catalytic kinetic system for the determination of vitamin P4 was established. The linear range was 0.01-0.9 mg / L, the detection limit was 8.9 × 10-3 mg / L, and the total rate constant of the catalytic reaction was 9.90 × 10-4 / s. This method can be used for the determination of Vitamin A in Weitailuutong tablet and Sophora japonica.