基于新型磁性固相萃取材料结合高效液相色谱法检测食品中碱性橙Ⅱ和柠檬黄

Determination of basic orangeⅡand tartrazine in food based on a new magnetic solid phase extraction material combined with high performance liquid chromatography

目的以Fe_(3)O_(4)/P[St-4-乙烯基吡啶(4-vinylpyridine,4-VP)]为磁性固相萃取材料,建立高效液相色谱法测定腐竹中碱性橙Ⅱ和苦荞茶中柠檬黄的分析方法。方法通过溶液pH、吸附时间、吸附方式、吸附剂用量和材料组成配比5个因素,优化了Fe_(3)O_(4)/P(St-4-VP)对色素的最佳吸附条件。通过等温吸附实验探究了Fe_(3)O_(4)/P(St-4-VP)的吸附模型。在优化的吸附条件下,结合高效液相色谱法定量分析了腐竹中的碱性橙Ⅱ和苦荞茶中的柠檬黄。结果Fe_(3)O_(4)/P(St-4-VP)对色素的最佳吸附pH:碱性橙Ⅱ为pH 7.0,柠檬黄为pH 3.0;最佳吸附时间、吸附方式、吸附剂用量和材料组成配比分别为5 min、振荡吸附、1.0 mg和Fe_(3)O_(4):P(St-4-VP)=2:1(m:m)。Fe_(3)O_(4)/P(St-4-VP)对碱性橙Ⅱ和柠檬黄的吸附过程均符合Langmuir等温吸附模型,最大吸附载量分别为116.5μg/mg和183.8μg/mg。将该材料应用于腐竹中碱性橙Ⅱ和苦荞茶中柠檬黄的检测,加标回收率为94.26%~101.04%,相对标准偏差为1.12%~3.35%(n=6)。结论Fe_(3)O_(4)/P(St-4-VP)对碱性橙Ⅱ和柠檬黄色素有较好的吸附性,可快速将色素从样品中分离,洗脱方便可回收,可用于腐竹中碱性橙Ⅱ和苦荞茶中柠檬黄的检测。

Objective To establish a method for the determination of basic orange II in bean curd stick and tartrazine in tartary buckwheat tea by using Fe_(3)O_(4)/P[St-4-vinylpyridine(4-VP)]as magnetic solid phase extraction material and high performance liquid chromatography.Methods The optimal adsorption conditions of Fe_(3)O_(4)/P(St-4-VP)for pigments were optimized through 5 factors:Solution pH,adsorption time,adsorption method,adsorbent dosage,and material composition ratio.The adsorption model of Fe_(3)O_(4)/P(St-4-VP)was investigated through isothermal adsorption experiments.Under the optimized adsorption conditions,the basic orangeⅡin bean curd stick and the tartrazine in tartary buckwheat tea were quantified by high performance liquid chromatography.Results The optimal pH for adsorption of pigments by Fe_(3)O_(4)/P(St-4-VP)were pH 7.0 for basic orange II,and pH 3.0 for tartrazine;the optimal adsorption time,adsorption method,adsorbent dosage,and material composition ratio were 5 min,oscillating adsorption,1.0 mg,and Fe_(3)O_(4):P(St-4-VP)=2:1(m:m),respectively.The adsorption processes of Fe_(3)O_(4)/P(St-4-VP)on basic orangeⅡand tartrazine conformed to Langmuir isothermal adsorption model,and the maximum adsorption load was 116.5μg/mg and 183.8μg/mg,respectively.The material was applied to the determination of basic orangeⅡin bean curd stick and tartrazine in tartary buckwheat tea.The recoveries were 94.26%‒101.04%,and the relative standard deviation was 1.12%‒3.35%(n=6).Conclusion The Fe_(3)O_(4)/P(St-4-VP)has good absorbability to basic orangeⅡand tartrazine,which can quickly separate the pigments from the samples,elute easily and be recycled,and can be used for the detection of basic orangeⅡin bean curd stick and tartrazine in tartary buckwheat tea.