基于铅离子诱导功能化核酸构象变化的氡累积浓度测定方法研究

发布时间：2018-01-02 18:05

本文关键词：基于铅离子诱导功能化核酸构象变化的氡累积浓度测定方法研究　出处：《南华大学》2016年硕士论文　论文类型：学位论文

更多相关文章：氡铅 核酸适体 DNAzyme G-四联体

【摘要】：氡是镭衰变产生的放射性气体,也是普遍存在于岩石和土壤之中的天然放射性核素。地质构造运动和人的活动制造了更多氡进入大气的途径,危害着人体健康。氡已经成为了肺癌的第二大诱因,时刻警醒着我们。现行的氡测量方法存在周期长、设备昂贵、对检测员有辐射伤害等问题。因此需要建立一个经济适用、灵敏度高、结果稳定可靠且无辐照危害的氡测量方法。第2章基于Pb2+-PW17-OG体系,建立了惰性气体氡的特异性非标记荧光传感的核酸适体检测新方法。OG结合游离卷曲的PW17产生强荧光;氡子体铅引入体系后,Pb2+诱导PW17形成稳定的G-四联体,抑制游离染料OG与PW17作用,体系荧光强度明显降低。在0.5~10μg/L的铅离子浓度范围内,体系荧光强度与铅离子浓度呈现良好的线性关系,与氡累积浓度(D)之间呈指数衰减关系。方法对铅离子的检出限为129.69ng/L。此方法避免了现场检测辐射损伤且灵敏、准确,开拓了核酸适配体对无机物、气体和放射性物质的生物分析新领域。第3章建立了硫磺素T和子体铅共同作用于G-四联体相互转化的氡浓度检测新方法。没有Pb2+离子存在的情况下,硫磺素T会自主的与适配体结合并诱导其形成顺式平行结构的G-四联体,而样品中存在的铅离子或铅标准溶液引入系统后会取代硫磺素T,G-四联体构象发生转变,导致荧光信号降低且会随着Pb2+离子浓度增加而逐渐减弱。体系的荧光强度与铅离子浓度在0.06~24μg/L范围内呈良好的线性关系,与氡累积浓度(D)之间呈指数衰减的关系。本方法Pb2+离子的检出限为23.03ng/L,氡的检出限为766.55Bq·h/m3。第4章基于DNAzyme对氡累积浓度检测的新方法研究。引入铅离子能够激活铅特异性DNAzyme,产生催化的作用导致底物链断裂游离,释放出来的单链DNA两两组合与硫磺素T结合形成G-四联体而荧光增强。荧光强度在0.12~4μg/L范围内与铅离子拥有良好的线性,检出限为97.14ng/L。对氡累积浓度检测得到的荧光强度与其呈对数增长的关系,检出限是947.50Bq·h/m3。
[Abstract]:Radon is a radioactive gas produced by radium decay, and is also a natural radionuclide in rocks and soils. Geological tectonic movements and human activities have created more radon into the atmosphere. Radon has become the second inducement of lung cancer and has been alerting us all the time. The current radon measurement method has a long period and expensive equipment. It is necessary to establish an economical, sensitive, stable and reliable radon measurement method based on Pb2 PW17-OG system. A new method for the detection of aptamer of nucleic acid by specific non-labeled fluorescence sensing of radon was established. OG combined with free curl PW17 produced strong fluorescence. After the introduction of radon progeny lead into the system, PB2 induces PW17 to form a stable G-tetraad, which inhibits the interaction between free dye OG and PW17. In the range of 0.5 渭 g / L lead ion concentration, there is a good linear relationship between the fluorescence intensity and lead ion concentration. The detection limit of lead ion is 129.69 ng / L. This method avoids the field detection of radiation damage and is sensitive and accurate. Nucleic acid aptamer pair inorganic compounds were developed. A new field of biological analysis of gases and radioactive materials. In Chapter 3, a new method for the detection of radon concentration in the interaction of sulfur T and lead in G- quadruple is established. There is no Pb2 ion. Sulfur T binds to the aptamer and induces it to form a cis-parallel G- tetraad. The lead ion or lead standard solution in the sample will replace the sulfur T when introduced into the system. The conformation of G-quadruple is changed. The fluorescence signal decreased and gradually weakened with the increase of Pb2 ion concentration. The fluorescence intensity of the system showed a good linear relationship with lead ion concentration in the range of 0.06 ~ (24 渭 g / L). The detection limit of Pb2 ion is 23.03 ng / L. The detection limit of radon is 766.55Bq 路h / m3. Chapter 4 is based on a new method of detecting radon accumulation concentration based on DNAzyme. Lead ion can activate lead-specific DNAzyme. The catalytic effect leads to the dissociation of the substrate chain. The released single strand DNA binds with sulfur T to form a G- tetraad and enhanced fluorescence. The fluorescence intensity is linear with lead ion in the range of 0.12 渭 g / L. The detection limit is 97.14 ng / L. The relationship between the fluorescence intensity and the logarithmic increase of radon accumulation concentration is 947.50 Bq 路h / m3.
【学位授予单位】：南华大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：R144.1

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