建立了蜂胶中多个重金属元素的快速测定方法。 选择正丙醇+二甲苯(体积比70∶30)稀释蜂胶后, 采用电感耦合等离子体质谱(ICP-MS)法直接分析稀释液中的Cr, Ni, As, Cd, Sb, Sn, Hg, Pb等重金属元素。 为防止稀释样品中高碳有机物的不完全燃烧在质谱锥口产生积碳, 通过在等离子工作气体中通入低浓度氧气使高碳有机物充分燃烧。 应用八极杆碰撞反应池(ORS)技术消除了多原子离子对待测元素产生的质谱干扰, 通过研究He碰撞气流速的变化对Cr, Ni, As预估检测限(EDL)的影响情况确定了最佳碰撞气流速, 采用单内标元素Rh消除了质谱基体效应, 维持了分析信号的稳定。 分析结果表明, 8个重金属元素的检出限在20.8～102.7 ng·L-1之间, 回收率为92.0%～109.0%, 相对标准偏差(RSD)≤3.5%。 方法可快速、 灵敏、 准确地测定蜂胶中8种重金属元素含量。

In current study, a method was established for simultaneous quantitative analysis of Cr, Ni, As, Cd, Sb, Sn, Hg and Pb in propolis by using inductively coupled plasma mass spectrometry. Before analyzed by ICP-MS, the propolis was diluted with n-propanol/xylene(70∶30, φ). Organic sample can remain stable by diluting with n-propanol/xylene, result from long-time sample dispersion in the solution. Carbon accumulation on the sampling cone, which comes from the high carbon content of butter, will clog the orifice and decrease analysis sensitivity. Thus a small amount of oxygen was added into the argon gas line to eliminate carbon. ORS was used to eliminate the polyatomic interferences caused by the high salty matrixes. The effects of the He collision gas flow rate on estimating detection limits of Cr, Ni and As were investigated. The matrix effects and the instrument drift have been calibrated with Rh as internal standard element. The results show that the detection limits is in the range of 20.8～102.7 ng·L-1, the recovery is in the range of 92.0%～109.0%, and the RSD is less than 3.5%. This method was simple, sensitive and precise to simultaneously analyze 8 heavy metal elements in propolis.