直接稀释-电感耦合等离子体质谱测定脐血清中22种元素

Direct determination for 22 kinds of elements in umbilical cord serum by ICP-MS

目的建立电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)测定人脐血清中22种元素含量的方法。方法吸取血清样本以2%硝酸15倍稀释,5000 r/min离心5 min,取上清液进样分析。用Ge作为内标元素校正八极杆碰撞模式定量元素(Fe、As、Se、I),用Sc、Ge、In、Bi作为标准模式定量元素的内标。ICP-MS射频功率1550 W,等离子气体流量15.00 L/min,进样量0.30 mL/min,驻留时间90 ms;八极杆反应气体为高纯He气,气体流速1.0 L/min,射频功率150 V,能量歧视5.0 V。结果内标标准曲线法定量,各元素在其线性范围内线性良好(r>0.9993),检出限为0.00158~1.21μg/L。质控血清测得值在标准值范围内。方法用于实际血清测定,加标回收率在86.4%~116%,测定精密度在0.164%~18.79%(n=6)。结论 ICP-MS法快速、灵敏、准确,操作简单,能有效地检测脐血清中各元素含量。

Objective A method for analysis of 22 kinds of elements in umbilical cord serum by inductively coupled plasma mass spectrometry（ ICP-MS） was developed.Methods The serum samples were taken out and diluted 15 times with 2% HNO3. After centrifugation for 5 min at 5000 r/min,the supernatant was injected into ICP-MS for analysis. Ge was used as internal standard element for correcting analysis of octopole collision model（ Fe,As,Se,I） and Sc,Ge,In,Bi were for standard model. ICP-MS analysis was performed on 1550 W of RF power,15. 00 L/min of plasma gas flow rate,0. 30 mL/min of sample injection volume and 90 ms of residence time. Octopole collision was carried out with He as reaction gas at 1. 0 L/min,150 V of octopole RF power and5. 0 V of energy discrimination. Results Internal standard curves were plotted for quantitative analysis and good linearity was obtained in their linear range（ r 0. 9993）and the limits of detection were 0. 00158-1. 21 μg/L. Control serum was analyzed withthe proposedmethod and theresult were in accordance with the standard values. The proposed method was applied to analysis of umbilical cord serum and the spiked recoveries were 86. 4%-116% with RSD of 0. 164%-18. 79%（ n = 6）. Conclusion ICP-MS is rapid,sensitive,accurate and simple. It can effectively determine the concentration of the elements in serum.