基于激光背向散射干涉的分子定量检测技术
发布时间：2018-08-19 19:39
【摘要】：近年来水污染、食品安全、疾病健康等问题日益突出,严重威胁着人类的健康。传统检测方法存在仪器体积较大、价格昂贵、操作复杂等问题,因此发展一种低成本、高灵敏度的生化检测技术成为当前的研究热点之一。背向散射干涉(Back-scattering interferometry,BSI)技术具有免标记、所需样品量小、检测限低、灵敏度高等优点,有望应用于食品检测、环境监测、临床诊断以及生化分析等领域中。将激光入射到通有待测物质的毛细管内,光在毛细管内外界面多角度的反射和折射,在环绕管轴360°范围内产生了干涉条纹,人们将其形象地称为“背向散射干涉”。当管内液体的折射率改变时,干涉条纹花样不变,但相对于初始干涉条纹有一定移动,根据移动量与折射率变化间关系,可实现折射率变化、抗原-抗体等分子间作用的测量。本文在BSI技术基础上,结合温度控制和快速傅里叶变换,搭建了一套基于BSI的高灵敏度定量分析与检测系统,并实现了微体积非吸光物质高灵敏度的定量检测;由于吸光物质吸收激光会产生光热效应,并引起溶液折射率的改变,因而该系统还可以用于微体积吸光物质的高灵敏定量检测。本文主要研究内容如下:1、采用温度控制系统和保温装置,实现了待测样品所处环境的温度的精确控制,使得检测过程中,样品不受周围环境温度波动的影响,实验过程中温度的波动仅有±0.007℃,提高了检测的分辨率和系统的稳定性,并通过Lab VIEW实现了数据的实时采集和自动化处理。2、通过对不同浓度的甘油和不同温度超纯水的检测,验证了该检测系统对非吸光物质的高灵敏度定量检测性能。基于红墨水溶液中的光热效应,对不同浓度品红墨水的光热信号进行了测量,结果表明该检测系统可用于对吸光物质的定量检测。3、过量的亚硝酸盐对人体健康具有极大的危害,因此对亚硝酸盐的定量检测具有重要的意义。利用改进的格里斯重氮化反应,使得亚硝酸盐通过显色反应转变为紫红色偶氮化合物,该化合物吸收绿色激光会产生明显的光热效应。采用波长为532 nm的激光作为激发光源,利用该化合物溶液的光热效应和BSI技术实现了亚硝酸盐浓度的定量检测;对自来水及加标自来水样中的亚硝酸盐进行了检测,并与紫外-可见光分光光度法的检测结果进行了对比,结果表明基于光热效应和BSI技术可实现亚硝酸盐的高灵敏度定量检测,使用3σ方法得到检测限为0.05 mg/L。
[Abstract]:In recent years, water pollution, food safety, disease health and other problems have become increasingly prominent, serious threats to human health. Traditional detection methods have many problems, such as large volume, high price and complex operation. Therefore, the development of a low cost and high sensitivity biochemical detection technology has become one of the current research hotspots. Back-scattering interferometry (BSI) has the advantages of low sample size, low detection limit and high sensitivity. It is expected to be used in food detection, environmental monitoring, clinical diagnosis and biochemical analysis. When the laser is incident into the capillary tube of the material to be measured, the reflection and refraction of light at various angles at the inner and outer interface of the capillary produces interference fringes in 360 掳range around the tube axis, which is vividly referred to as "backscattering interference". When the refractive index of liquid in the tube is changed, the pattern of interference fringes is invariable, but there is a certain movement relative to the initial interference fringes. According to the relationship between the amount of movement and the change of refractive index, the measurement of refractive index change and the interaction between antigen-antibody and other molecules can be realized. In this paper, based on BSI technology and temperature control and fast Fourier transform, a high sensitivity quantitative analysis and detection system based on BSI is built, and the quantitative detection of micro-volume non-absorbent material with high sensitivity is realized. The system can also be used for the sensitive and quantitative detection of microvolume absorbent materials because of the photothermal effect and the change of the refractive index of the solution when the absorbent laser absorbs the light. The main contents of this paper are as follows: 1. The temperature control system and the insulation device are used to realize the accurate control of the temperature of the environment in which the samples are to be tested, so that the samples are not affected by the ambient temperature fluctuations during the detection process. The temperature fluctuation in the experiment is only 卤0.007 鈩，
本文编号：2192633
[Abstract]:In recent years, water pollution, food safety, disease health and other problems have become increasingly prominent, serious threats to human health. Traditional detection methods have many problems, such as large volume, high price and complex operation. Therefore, the development of a low cost and high sensitivity biochemical detection technology has become one of the current research hotspots. Back-scattering interferometry (BSI) has the advantages of low sample size, low detection limit and high sensitivity. It is expected to be used in food detection, environmental monitoring, clinical diagnosis and biochemical analysis. When the laser is incident into the capillary tube of the material to be measured, the reflection and refraction of light at various angles at the inner and outer interface of the capillary produces interference fringes in 360 掳range around the tube axis, which is vividly referred to as "backscattering interference". When the refractive index of liquid in the tube is changed, the pattern of interference fringes is invariable, but there is a certain movement relative to the initial interference fringes. According to the relationship between the amount of movement and the change of refractive index, the measurement of refractive index change and the interaction between antigen-antibody and other molecules can be realized. In this paper, based on BSI technology and temperature control and fast Fourier transform, a high sensitivity quantitative analysis and detection system based on BSI is built, and the quantitative detection of micro-volume non-absorbent material with high sensitivity is realized. The system can also be used for the sensitive and quantitative detection of microvolume absorbent materials because of the photothermal effect and the change of the refractive index of the solution when the absorbent laser absorbs the light. The main contents of this paper are as follows: 1. The temperature control system and the insulation device are used to realize the accurate control of the temperature of the environment in which the samples are to be tested, so that the samples are not affected by the ambient temperature fluctuations during the detection process. The temperature fluctuation in the experiment is only 卤0.007 鈩，
本文编号：2192633
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