中文摘要：

以微波等离子体炬（MPT）作为离子源,廉价离子阱为质量分析器,建立了用常见有机质谱仪测定饮用水中微量钙的方法.实验考察了MPT工作气流量、载气流量等参数对待测元素信号的影响,并对这些参数进行了优化.在优化的实验条件下,采用标准加入法对井水、自来水及瓶装饮用矿泉水等样品中的微量钙进行了测定.结果表明,该方法的检出限（LOD）为3.88 ng/L,相对标准偏差（RSD）为2.87%~8.04%,加标回收率（R）为101.3%~115.1%.

英文摘要：

A method for the determination of trace-amount calcium in drinking water by common organic mass spectroscopy was developed. Meanwhile,microwave plasma torch was introduced as ionization source and lowcost ion trap was introduced as mass analyzer. The operation parameters including flow rates of working gas and carrying gas were studied and optimized. Under the optimal experimental conditions,the micro-amount calcium in well water,tap water and bottled water were determined. In order to minimize the matrix effects in the real samples,the standard addition analysis method was employed. The limit of detection was 3. 88 ng / L,and the relative standard deviations（ RSD） were 2. 87% —8. 04%. Recoveries were determined between101. 3% and 115. 1%. Experimental results indicated that the novel analytical strategy based on MPT-LTQMS for qualitation and quantitation of micro-amount calcium in drinking waters was simple and convenient.And its precision and accuracy meet the demand of determination. Furthermore,compared with ICP-MS,MPT-LTQ-MS was low-cost including instrument and maintenance. The proposed method is a novel and promising strategy for detection of micro-amount calcium in drinking waters.