高效液相色谱法测定食品中甲醛次硫酸氢钠含量

Determination of sodium formaldehyde sulfoxylate in food by high performance liquid chromatography

中文关键词:  甲醛次硫酸氢钠  高效液相色谱法  食品

英文关键词:sodium formaldehyde sulfoxylate  high performance liquid chromatography  food

中文摘要:

      目的 建立高效液相色谱法检测食品中的甲醛次硫酸氢钠含量。方法 样品经磷酸溶液提取, 残留在其中的甲醛次硫酸氢钠分解释放出甲醛, 甲醛与衍生试剂2,4-二硝基苯肼发生反应, 生成黄色的衍生物苯腙, 经Eclipse XDB-C18(250 mm×4.6 mm, 5 μm)色谱柱分离, 流动相为乙腈-水(60:40, V:V), 柱温为35 ℃, 流速为1.0 mL/min; 检测波长为355 nm, 经高效液相色谱仪检测。结果 本方法优化的实验条件是: 磷酸溶液浓度2.0%, 衍生剂2,4-二硝基苯肼溶液的浓度为2.0%, 60 ℃水浴中反应30 min; 甲醛标准溶液在0~3 μg/mL浓度范围内具有良好的线性关系(r=1.00); 在5、10和30 μg 3个加标水平上的回收率为95.36%~98.20%, 相对标准偏差为0.403%~1.05%; 检出限为0.17 mg/kg。结论 本方法快速准确, 适合于测定食品中甲醛次硫酸氢钠的残留量。

英文摘要:

      Objective To establish a method for determination of sodium formaldehyde sulfoxylate in food by high performance liquid chromatography (HPLC). Methods Samples were extracted with phosphoric acid solution, then the formaldehyde released from sodium formaldehyde sulfoxylate residues in samples and reacted with 2,4-dinitrophenylhydrazine (DNPH) for generating yellow 2,4-dinitrobenzene, which was separated with Eclipse XDB-C18 column (250 mm×4.6 mm,5 μm) with the mobile phase of acetonitrile-water (60:40, V:V) at 35 ℃, and the flow rate was 1.0 mL/min. The detection wavelength was set at 355 nm and then determined by HPLC. Results The optimization of the experimental conditions was that the concentration of phosphoric acid solution was 2.0%, and the concentration of 2,4-dinitrophenylhydrazine (DNPH) solution was 2.0% with 60 ℃ bathing for 30 min. The calibration curve of formaldehyde was linear within the range of 0~3 μg/mL (r=1.00). The recoveries of formaldehyde spiked at 3 levels of 5, 10 and 30 μg were 95.36%~98.20% and RSD were 0.403%~1.05%. The limit of detection was 0.17 mg/kg. Conclusion The method is rapid and accurate, which is suitable for detection of sodium formaldehyde sulfoxylate residues in food.