摘要
采用在线超滤-离子色谱法同时测定面粉中BrO3-、NO2-、NO3-3种阴离子的含量。10.00g样品用水超声提取30min,定容为100mL,离心分离,取上清液通过0.22μm在线超滤系统进行预处理。分取20μL进样,经Metrosep A Supp 7-250阴离子分析柱和Metrosep A Supp 4/5Guard保护柱分离,以3.6mmol·L-1碳酸钠溶液为流动相进行淋洗,采用抑制电导检测器进行检测。BrO3-、NO2-和NO3-分别在0.20~10.0 mg·L-1,0.02~2.00 mg·L-1和0.25~30.0mg·L-1范围内呈线性关系,检出限(3S/N)在0.20~2.50mg·kg-1之间。应用此方法分析了3个面粉样品,并以此为基体,用标准加入法进行回收试验,测得回收率在89.0%~110%之间,测定值的相对标准偏差(n=6)在2.2%~4.6%之间。
IC with inline ultra-filtration was applied to simultaneous determination of BrO3-,NO2-and NO3-in flour.The sample(10.00g)was extracted ultrasonically with water for 30min and the suspension was made up to 100mL and centrifuged.The supernatant was filtered with the 0.22μm inline ultra-filtration system. TwentyμL of the filtrate were separated on Metrosep A Supp 7-250separation column and Metrosep A Supp 4/5 Guard protective column,using 3.6mmol·L-1 Na2CO3solution as mobile phase.Inhibitory conductivity detector was adopted in the determination.Linear relationships were kept between values of peak area and mass concentration of BrO3-,NO2-and NO3-in the ranges of 0.20-10.0mg·L-1,0.02-2.00mg·L-1 and 0.25-30.0mg·L-1 respectively,with detection limits(3S/N)in the range of 0.20-2.50 mg·kg-1.Three flour samples were analyzed by this method,and recovery was tested by standard addition method,giving values of recovery and RSD′s(n=6)in the ranges of 89.0%-110%and 2.2%-4.6%respectively.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2014年第3期365-367,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
