OBJECTIVEThe purposes of this study were to investigate effects of chloroqquine (CQ) on inhibiting the decomposition of hydrogen peroxides (HP), and to optimize composition of the tooth-bleaching agent.

METHODSAccording to the principle of the color-changing reaction between horse radish peroxidase and substrate, the tooth-bleaching agent made of HP was divided into four groups with different amounts of CQ. The stability of HP was observed using ELISA for 3 months.

RESULTSWith the prolongation of store time, the absorbance of HP solutions containing different concentrations of CQ declined at different degrees, which showed a dependent relation between absorbance values and concentrations of CQ. Within the range of experiment concentrations of CQ, the higher the concentration of CQ was, the stronger the stability of HP was. And the duration of tooth-bleaching effects in 150.0 mg/ml of CQ was prolonged 4 to 6 times compared to that without CQ.

CONCLUSIONThe data indicate that CQ can inhibit the decomposition of HP. The bleaching effect of the tooth-bleaching agent which is made of HP and proper amount of CQ is satisfactory.