摘要
目的引入智能一体化蒸馏前处理方法,建立离子色谱-电导法测定小麦粉中双乙酸钠的检测方法。方法小麦粉样品采用智能一体化蒸馏仪蒸馏提取,蒸馏液用磷酸溶液调节pH值为3后定容,定容液经IonPac AS11阴离子交换柱分离,KOH淋洗液梯度淋洗,流速为1.0 ml/min,抑制性电导检测器检测,外标法峰面积定量。结果一体化蒸馏法可去除基质中不易挥发的离子,离子色谱-电导法可排除紫外末端吸收的干扰,提高了测定的准确性与灵敏度。该方法在0.004 mg/ml^0.05 mg/ml浓度时线性关系良好,相关系数(r)≥0.999,检出限为0.02 g/kg,采用低、中、高3个浓度加标,回收率在99.4%~102.2%,相对标准偏差(RSD)在1.37%~3.57%(n=6)。结论该方法操作简单快捷,重现性好,灵敏度高,可用于小麦粉中双乙酸钠含量的测定。
Objective An intelligent integrated distillation pretreatment method was introduced to establish a detection method for the determination of sodium diacetate in wheat flour by ion chromatography-conductivity method.Methods Wheat flour samples were extracted by intelligent integrated distillation apparatus.The distillate was adjusted to pH=3 by phosphoric acid solution and conducted for constant volume.The volume was adjusted by an IonPac AS11 anion exchange column.The KOH eluent was gradient eluted with a flow rate of 1.0 ml/min for the detection using a conductivity detector and the quantification of peak area by external standard method.Results The integrated distillation method can remove the non-volatile ions in the matrix.It can eliminate the interference of the ultraviolet end absorption by on chromatography with conductivity detection.It also can improve the accuracy and sensitivity of the measurement.The calibration curve showed a good linearity in the rage of 0.004 mg/ml-0.05 mg/ml with the correlation coefficient of greater than 0.999.At low,medium and high spiked levels,the recoveries of the method were within 99.4%-102.2%,and the relative standard deviation(RSD)was within 1.37%-3.57%(n=6).The minimum detection concentration was 0.02 g/kg.Conclusion The method is simple,rapid,reproducible and sensitive.It can be used for the determination of sodium diacetate in wheat flour.
作者
周楠
袁利杰
陈世伟
陈卓
刘颖
李海建
ZHOU Nan;YUAN Li-jie;CHEN Shi-wei;CHEN Zhuo;LIU Ying;LI Hai-jian(Food Inspection and Testing Institute of Henan Province,Zhengzhou,Henan 450002,China;不详)
出处
《中国卫生检验杂志》
CAS
2020年第1期9-11,共3页
Chinese Journal of Health Laboratory Technology
基金
河南省科技攻关项目(182102310064)
关键词
小麦粉
双乙酸钠
智能一体化蒸馏
离子色谱法
Wheat flour
Sodium diacetate
Intelligent integrated distillation system
Ion chromatography
