超高效合相色谱-串联质谱法测定口含烟中对羟基苯甲酸酯

建立了QuEChERS-超高效合相色谱-串联质谱法（UPC²-MS/MS）测定口含烟中对羟基苯甲酸酯类防腐剂。采用乙腈提取，基质分散固相萃取净化，UPC^{2 TM} HSS C18 SB色谱柱（3.0 mm×100 mm×1.8 μm）分离，内标法定量。优化后的对羟基苯甲酸酯的合相色谱分离条件为：主要流动相为CO₂，改性剂为甲醇-异丙醇混合溶液（V/V，1∶1），系统流速1.5 mL/min，离子化辅助溶剂（补偿溶剂）为0.1%甲酸-甲醇溶液，动态备压1.03×10⁷ Pa，柱温55 ℃，可在3 min内完成单个样品分析。4种成分的线性范围均为0.5~5.0 mg/kg；在低、中、高加标水平下，方法的平均回收率为94.6%~105.6%，相对标准偏差小于5%。实际样品测定结果表明，单个成分的含量和多种成分的总含量均小于10 mg/kg，低于GB 2760-2014对于此类防腐剂在食品中添加限量的要求。该方法环境友好、高效、准确，适用于口含烟中对羟基苯甲酸酯类物质的测定。

Determination of p-Hydroxybenzoic Esters (Parabens) in Snus by UPC2-MS/MS

An effective analytical method using QuEChERS coupled with ultra-performance convergence chromatography-tandem mass spectrometry (UPC²-MS/MS) for determination of p-hydroxybenzoic esters (parabens) in snus was developed. In the present work, acetonitrile was selected as extraction solvent, extraction kit (25 mg PSA, 7.5 mg Carbon, 150 mg MgSO₄) was evaluted to purify samples. The target analytes were separated on UPC^{2 TM} HSS C18 SB (3.0 mm×100 mm×1.8 μm) column, and quantified by internal standard method. The optimal separation conditions on UPC² were as follows: the main mobile phase was CO₂, and modifier was methanol-isopropanol (V/V, 1∶1), the flow rate was 1.5 mL/min, the assistant ionization solvent (compensate solvent) was methanol with 0.1% formic acid, the pressure of automated backpressure regulator (ABPR) was 1.03×10⁷ Pa, and the temperature of column was 55 ℃, the single analysis would complete within 3 min. The calibration curves are linear in the range of 0.5-5.0 mg/kg. The average recoveries of three addition levels are in the range of 94.6%-105.6% with RSD less than 5%. The detection results showed that parabens contents in snus are lower than the limits regulated by national standard GB 2760-2014 (<10 mg/kg). The proposed method is environmental friendly, high efficiency, accurate, which is suitable for analysis of parabens in snus.