微波消解–ICP–MS法测定话梅中的二氧化钛

Determination of Titanium Dioxide in Preserved Plum by Microwave Digestion-Inductively Coupled Plasma Mass Spectrometry

建立了微波消解-电感耦合等离子体质谱仪（ICP-MS）测定话梅中二氧化钛的方法。话梅样品用硝酸及过氧化氢经微波消解仪消解，将消解液除酸定容后用电感耦合等离子体质谱仪测定，以内标法测得钛的含量，并转换成样品中的二氧化钛含量。钛含量在0-500μg／kg范围内与信号强度呈良好的线性，线性相关系数r=0.9999，检出限为0.04μg／kg。在0.06，0.15，0.30μg／kg的添加水平下，加标回收率为80%-100%，相对标准偏差为3.2%-3.9%（n=6）。该法稳定性好，测定结果准确、可靠。

A method for the determination of titanium dioxide in preserved plum by microwave digestion-inductively coupled plasma mass spectrometry （ICP-MS） was established. Digestion of preserved plum with HNO3 and H2O2 was carried out in microwave digestion instrument. After acid being removed, the digestion solution was diluted to an constant volume and detected by inductively coupled plasma mass spectrometry（ICP-MS）, quantified with internal standard, and then the content of titanium was gotten. The content of titanium dioxide could be calculated by the content of titanium. The detection limit of titanium dioxide was 0.04 μg/kg. The content of Ti was linear with signal strength in the range of 0-500 μg/kg, the correlation coefficient was 0.999 9. The recoveries of itanium dioxide in preserved plum ranged from 80%to 100%, as the spiked levels were 0.06,0.15 and 0.30μg/kg. The relative standard deviation was 3.2%-3.9%（n=6）. The mothod is reliable, accurate and stable.