基于数字微镜器件的原子荧光信号增强技术研究  

Study on Signal Enhancement Technology for Atomic Fluorescence Spectrometry Based on Digital Micromirror Device

作　　者：王宏霞[1] 李颖超 李春生[1] 周志恒 马振予 田地[1] WANG Hong-Xia;LI Ying-Chao;LI Chun-Sheng;ZHOU Zhi-Heng;MA Zhen-Yu;TIAN Di(College of Instrumentation&Electrical Engineering,Jilin University,Changchun 130061,China;Beijing Bohui Innovation Biotechnology Co.,Ltd,Beijing 102206,China;Changchun Institute of Optics and Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China)

机构地区：[1]吉林大学仪器科学与电气工程学院,长春130061 [2]北京博晖创新生物技术股份有限公司,北京102206 [3]中国科学院长春光学精密机械与物理研究所,长春130033

出　　处：《分析化学》2021年第9期1470-1477,I0001-I0002,共10页Chinese Journal of Analytical Chemistry

基　　金：国家重点研发计划重大科学仪器设备开发专项课题项目(No.2016YFF0103303)资助。

摘　　要：在氢化物发生-原子荧光光谱仪(HG-AFS)非色散检测系统基础上,增加基于紫外数字微镜器件(DMD)的色散检测系统,当测试样品存在光源光谱干扰或散射干扰时,选择色散系统检测样品,可以有效抑制干扰。由于增加了分光部件,色散系统的检出限(LOD)性能降低。为提高色散检测法的分析性能,本研究在光电倍增管(PMT)前增加柱面镜和扩大光电倍增管的最小有效区域,以增强信号强度,针对DMD翻转检测提出了定点模式,优化了元素检测时谱峰选取等分析方法,并对影响信号强度的仪器参数进行了优化。结果表明,本系统使180~320 nm范围内信号的检测强度提高至2倍以上,光谱分辨率提高至1.2倍以上,同时获得了Cd、Te、Sn和Zn的光源发射谱线和激发荧光谱线。利用本系统测试了10种HG-AFS常测元素,其中,Cd的检出限低于0.005 ng/mL,Sn的检出限低于0.02 ng/mL,Sb、Pb和Te的检出限低于0.05 ng/mL,As、Bi和Hg的检出限低于0.1 ng/mL,Se和Zn的检出限低于0.2 ng/mL。将此系统用于检测生活饮用水中As的浓度,加标回收率为93%~101%,RSDs为0.6%~3.3%,实际食品样品中As的加标回收率为95%~106%,RSDs为0.9%~3.4%。通过对紫外DMD光谱仪的改进、DMD翻转检测模式的升级以及分析方法的优化,有效改善了色散检测系统的检出限和分辨率,其检测能力满足生活饮用水卫生标准(GB 5749-2006)毒理指标限值的检测需求,在实际食品样品检测中也具有良好的检测准确度、灵敏度及稳定性。A dispersive detection system based on ultraviolet digital micromirror device(DMD)was used for hydride generation atomic fluorescence spectrometer(HG-AFS)on the basis of the original non-dispersion detection system.The dispersion system was used to suppress the interference when spectral interference from the light source or scattering interference exists.The limit of detection(LOD)of the dispersive system was worse than the non-dispersive one due to the addition of the dispersive components(DMD and grating,etc).In this work,to improve the analytical performance of the dispersive detection method,a cylindrical mirror was installed in front of the photomultiplier tube(PMT),the minimum effective area of the PMT was expanded to enhance the signal intensity,a better fixed location mode of DMD rotation was proposed,and the analysis methods such as peak selection and the instrument parameters affecting the signal intensity were optimized.The results showed that the signal intensity within 180-320 nm was increased more than 2 times,and the spectral resolution was increased more than 1.2 times.Moreover,the emission lines and excitation fluorescence lines of Cd,Te,Sn and Zn were obtained,and the LODs were respectively less than 0.005 ng/mL for Cd,0.02 ng/mL for Sn,0.1 ng/mL for As,Bi and Hg,0.05 ng/mL for Sb,Pb and Te,and 0.2 ng/mL for Se and Zn.The spiked recoveries and the RSDs of As were 93%-101%and 0.6%-3.3%in living and drinking water samples,and 95%-106%and 0.9%-3.4%in food samples,respectively.The LOD and resolution of the dispersive system were effectively improved because of the improvement of the ultraviolet DMD spectrometer,the upgrade of the DMD rotation detection mode and the optimization of the analysis method.As a result,the dispersive system met the detection requirements of toxicological index limits in the Standards for Drinking Water Quality(GB 5749-2006),and also had good accuracy,sensitivity and stability in actual food sample analysis.

关 键 词：氢化物发生-原子荧光光谱仪 信号增强 数字微镜器件 色散检测 

分 类 号：R123.1[医药卫生—环境卫生学] R155.5[医药卫生—公共卫生与预防医学] O657.3[理学—分析化学] TS207.3[理学—化学]