全自动固相萃取/超高压液相色谱测定食品中合成色素

建立了全自动固相萃取/超高压液相色谱法同时测定食品中10种人工合成色素柠檬黄、苋菜红、胭脂红、日落黄、亮蓝、诱惑红、靛蓝、赤藓红、新红、酸性红的方法。液体样品经加热驱除二氧化碳和酒精,固体或半固体样品经乙醇-水-氨水(70+29+1)溶液提取,所得待净化液采用全自动固相萃取仪经Strata X-AW SPE小柱净化,采用超高压液相色谱进行分析。用甲醇和0.02 mol/L乙酸铵溶液作为流动相进行梯度洗脱,流速0.3 mL/min,在4 min内实现10种合成色素的良好分离。10种色素在1~50μg/mL的范围内线性良好。10种色素的方法最低检出限是0.004 mg/kg,加标回收率在83.8%~111.2%之间,相对标准偏差在1.24%~4.18%之间(n=6)。本方法操作简单,灵敏度高,干扰少,能满足食品中多种合成色素同时分析测定要求。

Determination of Synthetic Colorants in Food by Automatic Solid Phase Extraction/UPLC

An automatic solid phase extraction/ultra high pressure liquid chromatographic method was established for the simultaneous determination of 10 synthetic colorants tartrazine, amaranth, ponceau 4R, sunset yellow, brilliant blue, allura red, indigotine, erythrosine, new red, and carmoisine in food.Liquid samples were removed carbon dioxide and alcohol by heating , solid or semi-solid samples were extracted with alcohol -water-ammonia （ 70＋29＋1 ） solution , and the extract was purified on Strata X -AW SPE column by automatic solid phase extraction apparatus , than analyzed by UPLC.The mobile phase was methanol and 0.02 mol/L ammonium acetate solution in gradient condition.The flow rate was 0.3 mL/min.Using the best gradient condition , ten synthetic colorants achieved the grate separation in 4 min.All the ten synthetic colorants had a good linearity in a concentration range of 1 -50 μg/mL.The detect limit of the method was 0.004 mg/kg.The spiked recoveries of ten colorants ranged from 83.8% to 111.2%, with the RSDs of 1.24%-4.18%（ n =6 ）.This method was simple , sensitive and anti -interfere , which can be used for the determination of multiple synthetic colorants in food.