摘要
针对As(Ⅲ)的检测问题,提出了一种基于适配体-金纳米粒子探针和光热-激光背向散射干涉原理的水中As(Ⅲ)的定量检测技术。结合了As(Ⅲ)适配体的金纳米粒子溶液呈现稳定的酒红色,对绿光有较强的吸收作用。采用532 nm的激光照射毛细管内的金纳米粒子溶液,由于光热效应溶液折射率发生变化,激光背向散射干涉(Back-Scattering Interference,BSI)产生的干涉条纹就会发生移动。待测溶液中存在As(Ⅲ)时,As(Ⅲ)与适配体相结合,导致适配体从金纳米粒子颗粒表面脱落,在高浓度盐的作用下,金纳米粒子颗粒聚集,溶液的颜色由酒红色变成蓝紫色,光热效应引起的干涉条纹移动量减小。建立As(Ⅲ)浓度与干涉条纹移动量之间的关系,通过检测干涉条纹的移动量实现了水中As(Ⅲ)的定量检测,检出限为0.127 mg/L。
A quantitative detection technique based on aptamer-Au nanopaticle probe(aptamer-Au NPs)and photothermal-laser backscattering interference(PT-BSI)was developed for the detection of trivalent arsenic(As(Ⅲ))in water.The Au NPs covered with aptamers could be dispersed well in solution.The solution showed a wine-red color,which has strong absorption to green light.A laser with the wavelength of 532 nm was used to illuminate the aptamer-Au NPs solution in a capillary.The refractive index of the solution changed due to the photothermal effect,leading to the shift of the interference fringe by PT-BSI.In the presence of As(Ⅲ),the aptamer formed an aptamer-As(Ⅲ)complex probe,the Au NPs were no longer covered with aptamer and therefore were subjected to NaCl-induced aggregation.The aggregation of Au NPs led to a color change of Au NPs from wine-red to purple-blue,and the shift of interference fringe decreased due to the weaken photothermal effect.Through the relationship between As(Ⅲ)concentration and the shift of interference fringe,the As(Ⅲ)in the water can be detected with a limit of detection of 0.127 mg/L(127 ppb),and the limit can be further reduced by optimizing experimental parameters.
作者
田耀宗
张校亮
谭慷
李晓春
TIAN Yaozong;ZHANG Xiaoliang;TAN Kang;LI Xiaochun(Key Laboratory of Advanced Transducers and Intelligent Control System Ministry of Education and Shanxi Province,College of Physics and Optoelectronics,Taiyuan University of Technology,Taiyuan 030024;College of Biomedical Engineering,Taiyuan University of Technology,Taiyuan 030024)
出处
《分析科学学报》
CAS
CSCD
北大核心
2021年第1期29-34,共6页
Journal of Analytical Science
基金
国家自然科学基金(No.61775157,21874098)
山西省应用基础研究青年基金(No.201801D221194)
山西省重点研发计划(高新领域)(No.201903D121158)
山西省高等学校科技成果转化培育项目
山西省高等学校优秀青年学术带头人支持计划项目。
