微波消解-电感耦合等离子体质谱法测定 大豆油（供注射用）中14种金属元素Determination of 14 kinds of metal elements in soybean oil (for injection) by microwave digestion-inductively coupled plasma mass spectrometry

旨在为大豆油（供注射用）的质量控制及安全评价提供参考，建立了微波消解-电感耦合等离子体质谱( ICP-MS)法测定大豆油（供注射用）中金属元素含量。将0.5 g大豆油（供注射用）加硝酸溶解后，先在100 ℃预消解1 h,再采用微波消解仪进行前处理，通过ICP-MS法在射频功率1 550 W、载气（高纯氩气）流速1.03 L/min、等离子气体流速15.0 L/min、蠕动泵转速0.1 r/s、采样深度10 mm条件下测定14种金属元素含量。应用四极杆碰撞/反应池技术消除多原子离子对待测元素的干扰，以钪(Sc)、锗(Ge)、铟(In)、铼(Re)元素为内标校正基体干扰和漂移。结果表明：该方法14种金属元素的检出限在0.004～0.283 ng/mL之间，定量限在0.012～0.945 ng/mL之间，线性关系良好，相关系数均大于0. 999；仪器精密度良好，相对标准偏差（RSD）在0.38%～5.03%之间，重复性RSD在1.02%～4.62%之间，中间精密度RSD在1.40%～16.21%之间，样品溶液在2～8 ℃条件下保存3 d，稳定性良好，储存期间RSD在0.54%～9.61%之间;低、中、高3个水平的加标回收率在78.87%～112.07%之间，RSD在1.37%～7.08%之间。综上，该方法快速、准确、灵敏度高,可用于大豆油（供注射用）中14种金属元素的同时检测。 Aming at providing reference for the safety control and security evaluation of soybean oil (for injection), a method for the determination of metal elements content in soybean oil (for injection) by microwave digestion-inductively coupled plasma mass spectrometry(ICP-MS) were developed. 0.5 g soybean oil (for injection) was dissolved in nitric acid and then predigested at 100 ℃ for 1 h, pretreated in microwave digestion instrument and measured with ICP－MS under the conditions of radio frequency power 1 550 W, flow rate of carrier gas (high purity argon) 1.03 L/min, flow rate of plasma gas 15.0 L/min, peristaltic pump speed 0.1 r/s and sampling depth 10 mm to determine the content of 14 kinds of metal elements. The use of quadrupole collision/reaction cell technology could eliminate the interference of polyatomic ions with the elements to be measured. Scandium (Sc), germanium (Ge), indium (In) and rhenium (Re) were used as internal standards to correct matrix interference and drift. The results showed that the detection limits of 14 kinds of metal elements were in the ranges of 0.004-0.283 ng/mL.The quantitation limits were 0.012-0.945 ng/mL.The linear relationship for the elements was good with the correlation coefficients being all above 0.999．The precision of the instrument was good and RSD were 0.38%-5.03%. The repeatability RSD were 1.02%-4.62%. The intermediate precision RSD were 1.40%-16.21%. The stability of the sample solution was good when it was stored at 2-8 ℃ for 3 d, with RSD in the range of 0.54%-9.61%. The recoveries of the 14 kinds of metal elements at three levels（low, medium and high）were 78.87%-112.07% and the RSD were 1.37%-7.08%. In summary, the method is rapid, accurate and sensitive, and it can be used for the simultaneous detection of 14 kinds of metal elements in soybean oil (for injection).