Kinetic determination of GA by the BZ oscillating chemical system

A new analytic method for the determination of gibberellic acid (GA) by perturbation causing different amounts of GA on the BZ oscillating chemical system involving the Mn(II)-catalyzed reaction between L-alanine, potassium bromate, and malonic acid in the acidic medium is proposed. The method relies on the linear relationship between the change in the oscillating period of the chemical system and the concentration of GA, which is in this work exposed for the first time. The calibration curve is linearly proportional to the concentration of GA over the range 1.0 x 10(-8) -1.0 x 10(-6) M, where the regression coefficient is 0.9998, and the detection limit is 5.0 x 10(-9) M of GA. Some aspects of the potential mechanism of action of GA on the BZ oscillating chemical system are discussed in detail.