Determination of paracetamol by chemiluminescence with KMnO ₄-calcon-rhodamine B

Objective: To establish a rapid and precise continuous flow-injection chemiluminescence for the determination of paracetamol. Methods: In acid solution, calcon could be oxidized by KMnO₄ producing a weak chemiluminescence, and great chemilumimescence was obtained with the presence of rhodamine B. Then the signal was inhibited with the presence of paracetamol. The inhibitor intensity was linear with the concentration of paracetamol. Coupled with the flow injection technique, a rapid flow injection chemiluminescence method was developed for the determination of paracetamol. The parameters affecting the chemiluminescence signal were investigated. Results: Under the optimized conditions, the linear range was 5.0 × 10^-7 - 1.0 × 10^-5 g/mL. The detection limit was 7.0 × 10 ^-8 g/mL with a signal-to-noise ratio of 3:1. The RSD of 11 times parallel assays for 1.0 × 10^-6 g/mL paracetamol was 2.2%. Conclusion: The method is simple, rapid and precise, and satisfactory results were obtained with the method applied for the pharmaceutical preparations of paracetamol.