微流动注射进样-加热雾室-等离子体质谱测定血清中的铂

开发了一种基于雾化室加热的微流动注射进样系统，并用于血清中Pt的测定。该进样系统由微量毛细管雾化器、加热微型雾化室、八通道十六孔多功能旋转阀、蠕动泵和注射泵组成。研究了雾化室尺寸、加热温度和采样环体积对信号强度的影响。当雾化室内径为9 mm、加热段长度为6 cm，雾化室温度90 ℃，采样环体积为5 μL时，195Pt的信号强度提高了2.31倍，同时信号精密度从5.1%降至2.2%，并得到峰形良好的信号峰。该进样系统的试样消耗小、灵敏度和检出限均优于常规进样系统。10次测定10 μg/L的Pt标准溶液和血清样品溶液，峰高的RSD分别为2.9%和3.3%。该进样系统测得10个血清中的Pt含量与常规进样系统的测试结果无显著差异，在样品量稀少的情况下具有良好的应用价值。

Determination of Platinum in Serum Samples by Inductively Coupled Plasma Mass Spectrometry with Microscale Flow Injection Based on a Heated Spray Chamber

A heated single pass spray chamber-based microscale flow injection sampling system was developed for the analysis of platinum in serum samples by inductively coupled plasma mass spectrometry.It consisted of a homemade demountable capillary microflow nebulizer,a single pass spray chamber heated by means of resistive heating,an eight channel sixteen-port multifunctional injector valve and a syringe pump equipped with a 10-mL syringe as well as a peristaltic pump.Effects of the dimensions of spray chamber,the heating temperature and the sampling loop volume on the intensity were investigated.The maximum intensity were obtained with the single pass spray chamber with an inner diameter of 9 mm and a length of 6 cm for the heated section.When it was heated up to 90 ℃ and the sampling loop volume was selected to be 5 μL,the intensity of 195Pt was enhanced by a factor of 2.31 and the precision of transient signals for 195Pt was reduced from 5.1% to 2.2%,a signal peak with good configuration was obtained.Compared with the conventional sampling system,the heated single pass spray chamber-based microscale flow injection sampling system offers a little better sensitivity and detection limit in the case of lower sample consumption.The relative standard deviations of peak heights of 10 replicate trials of 10 μg/L standard solution and a serum sample were 2.9% and 3.3%,respectively.The contents of platinum in serum samples by the proposed method agreed well with those obtained by the conventional sampling system.The heated single pass spray chamber-based microscale flow injection sampling system can be applied in many fields,especially in the case of limited or rare samples.