采用解吸电晕束电离源(DCBI)与质谱联用法测定食品包装材料中的双酚A。优化了萃取溶剂和离子源等参数。DCBI优化后,甲醇为萃取溶剂,检测模式为负离子模式,电离电压为-2kV,离子传输管温度225℃,He气体流速1.0L/min。当选用全扫描的模式时,单个样品测定时间小于30s,对双酚A的检出限为0.1mg/L,在1—100mg/L浓度范围内线性良好,相关系数达到0.98,直接检测食品包装材料中的双酚A时,平均回收率为94%~125%,测定结果的相对标准偏差(RSD)小于17%。本方法分析速度快,灵敏度高,基体影响小,适用于大量样品快速检测。
A novel method, based on desorption corona beam ionization (DCBI) tandem mass spectrometry (MS), was developed for the direct detection of bisphenol A in food packaging materials with minimal sample pretreatment. We optimized DCBI-MS conditions (i. e. extraction solvent and ionization source ) using representative bisphenol A standards. The reagent solvent was methanol at high voltage (-2.0 kV, negative ion detection mode). The temperature of the heated capillary was optimized to be 225 ℃. The flow rate of He was 1.0 L/min. The limit of detection (LOD) of these amino acids was 〈 0.1 mg/L, and the linear dynamic range was 1-100 mg/L. The bisphenol A concentration in food packaging material samples was measured by the method, and the average time for a single sample analysis was less than 30 s. The recovery rates for different concentrations ranged from 94% to 125%, and the relative standard deviation (RSD) was less than 17%. This study showed that DCBI-MS was a powerful tool for the rapid, sensitive, and quantitative detection of bisphenol A amino acids in complex meterials samples.