响应面分析法在HR-ICP-MS仪器参数优化中的应用

摘要

通过响应面分析法,对辅助气流量、雾化气流量和采样深度三个影响高分辨感耦等离子体质谱仪测定灵敏度的主要仪器参数进行了系统优化.应用中心组分设计得到了覆盖整个质量数范围和低、中、高三种分辨率模式的信号强度响应值,经过多项式回归运算建立信号平均值的数学模型,模型整体对响应值高度显著,R2 =0.9944.通过典型分析,得到在全质量数范围内的最优仪器参数为:辅助气流量为0.56 L/min;雾化气流量为0.95 L/min;采样深度为-2.3 mm,所得响应面及等高线图直观地显示了仪器参数之间的交互影响作用.响应面分析法通过较少的实验次数,得到了更加科学、合理的仪器最优化参数.%Sample gas,auxiliary gas and Z-position,which could affect the determination sensitivity of high resolution inductively coupled plasma mass spectrometry,were optimized by response surface methodology.Involving the whole mass range and the resolution mode of low,middle and high,signal intensity response values were obtained by using central composite design.Using polynomial regression operation,mathematics model of signal average values was established,and the total model was significant at 99％ confidence level,R2 =0.994 4.Through canonical analysis of response surface,the best operating parameters of HR-ICP-MS were:auxiliary gas =0.56 L/min,sample gas =0.95 L/min and Z-position=-2.3 mm,respectively.The interaction of parameters could be distinctly revealed by response surface and contour diagrams.Using less amount of experiment,the best operating parameters obtained by response surface methodology were more reasonable and scientific.