After The Research And Application Of The Oxidation Of The Role Of Benzoyl-and ¦Â-cyclodextrin Supramolecular Spectrophotometry

The property of benzoyl peroxide and its application in chemical industry,medicine industry and foodstuff were reviewed in this paper systematically .The degradation mechanism of benzoyl peroxide was studied at different temperatures and pH values with spectrophotometry. It was found that the degradation rate of BPO increased with the rising of pH values,in the range of pH=4-10,it was a second-rate reaction; the degradation rate of BPO decreased with the rising of temperature,The test showed that the procedure was a heat liberation reaction, and it was a second-rate reaction, too.A novel method for determination of benzoyl peroxide with spectrophotometry was developed. Inclusion ratio of β cyclodextrin to dibenzoy peroxide and benzoic acid is obtained with spectrophotometry.The mechanism of the inclusion was studied,too. The results showed that β-CD react with dibenzoyl peroxide to form a 1:1 or 2:1 host-guest complex, with the apparent formation constants of 5.0× 10~2and 2.5× 10~4 , respectively. β-CD reacts with benzoic acid to form a 1:1 host-guest complex with the apparent formation constant of 6.9 × 10~2 after the dibenzoyl peroxide was reduced by hydroxyl ammonium chloride. Based on the enhancement of the absorbance of dibenzoyl peroxide produced through complex formation, a spectrophotometric method for determination of dibenzoyl peroxide in bulk aqueous solution in the presence of β-CD was developed. A linear relationshipbetween the absorbance and dibenzoyl peroxide concentration was obtained in the range of 0.2- 50 μg.ml-1. Linear regression equation of the calibration graph was A=0.02926+53.2543C, with a correlation coefficient of 0.9984 and a relative standard deviation of 3.4%. The detection limit was 0.2 μg.ml-1, and the recovery were from 98.0 to 105.0 %. The proposed method was used to determine the dibenzoyl peroxide in the flour with satisfactory results. The principal advantage of the proposed method is its excellent selectivity based on molecule recognition of β-CD and simple.