Zhao Yansheng, Yang Minli, Zhang Feng, Feng Feng, Chu Xiaogang, Dong Ying
Chinese Academy of Inspection and Quarantine, Beijing 100123, China.
Se Pu. 2011 Jul;29(7):631-6.
A screening method for 29 forbidden or limited synthetic pigments in cheese samples was established by liquid chromatography/quadrupole time-of-flight mass spectrometry (LC/Q-TOF MS). The pigments were extracted by n-hexane/water (3:1, v/v). After extraction, the n-hexane extract, water extract and residue, were obtained. The n-hexane extract was then cleaned-up by gel permeation chromatography (GPC). The water extract was extracted by acetonitrile, and the residue by ammonia water/methanol (1:99, v/v). The results showed that the 29 synthetic pigments with a wide range of polarities were extracted effectively with the recoveries between 70% and 95%, and matched well by Q-TOF MS precision mass searching to the mass spectral library with matching scores between 59. 66 and 99. 47. The quantitative analysis of the 29 pigments was carried out by Target MS/MS. The limits of detection (LODs) for 8 Sudan dyes were 0.4-2.5 micro/kg while for 21 water-soluble synthetic pigments were 20-80 microg/kg. The screening method is suitable for a wide range of synthetic pigments, and can be applied to food samples with proteins and fat in matrix.
建立了一种采用液相色谱/四极杆飞行时间质谱（LC/Q-TOF MS）测定奶酪样品中29种禁用或限用合成色素的筛查方法。色素用正己烷/水（3:1，v/v）提取。提取后，得到正己烷提取物、水提取物和残渣。正己烷提取物再通过凝胶渗透色谱（GPC）进行净化。水提取物用乙腈提取，残渣用氨水/甲醇（1:99，v/v）提取。结果表明，29种极性范围广泛的合成色素得到了有效提取，回收率在70%至95%之间，通过Q-TOF MS精确质量搜索与质谱图库匹配良好，匹配分数在59.66至99.47之间。采用目标MS/MS对29种色素进行定量分析。8种苏丹染料的检测限（LOD）为0.4 - 2.5微克/千克，21种水溶性合成色素的检测限为20 - 80微克/千克。该筛查方法适用于多种合成色素，可应用于基质中含有蛋白质和脂肪的食品样品。
