过氧化氢-茚三酮体系荧光光度法检测食品中的焦磷酸盐  

Fluorescence Spectrophotometric Method for the Detection of Pyrophosphates in Food Samples with Hydrogen Peroxide-Ninhydrin System

作　　者：熊海涛[1,2] 徐艺凤 徐承娥 Xiong Haitao;Xu Yifeng;Xu Chenge(Shaanxi Key Laboratory of Catalysis,Shaanxi University of Technology,Hanzhong 723001,Shaanxi;School of Chemical&Environmental Sciences,Shaanxi University of Technology,Hanzhong 723001,Shaanxi)

机构地区：[1]陕西理工大学陕西省催化基础与应用重点实验室,陕西汉中723001 [2]陕西理工大学化学与环境科学学院,陕西汉中723001

出　　处：《中国食品学报》2023年第7期374-381,共8页Journal of Chinese Institute Of Food Science and Technology

基　　金：陕西省科技厅自然科学基金项目(2018JQ2057);国家级大学生创新创业训练计划项目(202110720022)。

摘　　要：摄入过多的焦磷酸盐会对人体健康产生严重影响,因此控制食品中焦磷酸盐的含量十分重要。在酸性介质中,Cu^(2+)能催化过氧化氢-茚三酮体系间的氧化-还原反应而产生较强的荧光。当在该体系中加入少量焦磷酸盐后,Cu~(2+)-H_(2)O_(2)-茚三酮体系的荧光强度显著减弱。基于此,建立一种荧光光度法检测焦磷酸盐含量。考察过氧化氢浓度、茚三酮浓度、Cu^(2+)浓度、反应时间及反应温度等条件对荧光强度的影响。结果表明,最优条件为过氧化氢浓度3.0×10~(-5)mol/L,茚三酮浓度2.0×10~(-3)mol/L,Cu~(2+)浓度6.0×10~(-5)mol/L,反应时间40 min,反应温度30℃,在此条件下,减弱的荧光强度与焦磷酸盐浓度在3.0×10-7~8.0×10~(-6)mol/L范围内的对数值呈良好的线性相关。方法的检出限与相对标准偏差(RSD)分别为3.2×10~(-8)mol/L,4.9%(C=1.0×10~(-6)mol/L,n=11)。采用该方法测定虾仁与带鱼样品中焦磷酸盐含量并做加标回收试验,平均回收率在93.00%~97.80%范围,表明该方法可用于实际食品样品中焦磷酸盐含量的准确检测。Pyrophosphate can seriously affect human health.Therefore,it is necessary to control the content of pyrophosphate in food.In the acid medium,copper ion(Cu^(2+))can effectively catalyze the redox reaction between hydrogen peroxide and ninhydrin,leading to produce a strong fluorescence.When a small amount of pyrophosphate was added into the hydrogen peroxide-ninhydrin system,the above-mentioned fluorescence was obviously reduced.Based on this observation,a fluorescence strategy for the quantitative analysis of pyrophosphate was developed.Several experiment parameters,such as hydrogen peroxide concentration,ninhydrin concentration,Cu^(2+) concentration,reaction time and reaction temperature were optimized to investigate the effect of these factors on the fluorescence intensity.The result showed that,the optimized experimental conditions was set as follows:3.0×10^(-5)mol/L of hydrogen peroxide,2.0×10^(-3)mol/L of ninhydrin 6.0×10^(-5)mol/L of copper ion,40 min of reaction time and reaction temperature at 30℃.Under the conditions,the relative fluorescence intensity displayed a good linear relationship with the logarithm value of pyrophosphate concentration in the range of 3.0×10-7-8.0×10^(-6)mol/L.And the detection limit and the relative standard deviation were 3.2×10^(-8)mol/L and 4.9%(C=1.0×10-6 mol/L,n=11),respectively.The content of pyrophosphate in the shelled shrimp and hairtail samples were quantified by the proposed method,and the average recoveries were between 93.00%and 97.80%.This result showed that the developed method can be applied in the accurate detection of pyrophosphate content in the practical food samples.

关 键 词：茚三酮 过氧化氢 Cu(Ⅱ) 焦磷酸盐 荧光光度法 

分 类 号：O657.3[理学—分析化学] TS207.3[理学—化学]