碘化钾-吖啶红体系光度法测定小麦面粉中的过氧化苯甲酰

摘要

The spectrophotometric determination of benzoyl peroxide(BPO) in wheat flour by KI-Acridine Red- PVA system was established. It was found that in the H2SO4 medium, BPO reacts with KI to give 13- , which further reacts with acridine red to form an ion-association complex and causing the absorbance of the solution decreased. Un- der 525nm, a good linear relationship was found between the absorbance and concentration of BPO and the average re- covery was 98.2% and 101.6% respectively. Based on these facts, a simple sensitive and accurate spectrophotomet- rie method for the determination of BPO was proposed. It has the advantages including easy operation, high sensitivi- ty, good precision, and low consumption etc. , which can meet the requirements to detect benzoy peroxide residue in wheat flour samples.%采用碘化钾-吖啶红分光光度法对小麦面粉中过氧化苯甲酰含量进行了测定。在硫酸介质中,有聚乙烯醇存在的情况下,过氧化苯甲酰氧化I-生成I3-,I3-与吖啶红发生离子缔合反应,导致KI-吖啶红-聚乙烯醇溶液体系的吸光度下降,在525 nm波长下,过氧化苯甲酰在0.04～6.0 mg/L内与吸光度的改变量呈线性关系,据此建立了测定小麦面粉中过氧化苯甲酰的碘化钾-吖啶红分光光度法,该法用于小麦面粉中过氧化苯甲酰的测定,平均回收率为98.2%与101.6%。