一种用于细胞核成像的新型双光子荧光探针

本文报道了具有大双光子活性吸收截面的DNA探针BMVEC, 同时首次利用双光子显微镜完成了与DAPI的复染实验, 实验结果证实了BMVEC对细胞核的选择性标记能力.     

一种基于分子信标荧光探针快速检测烟草花叶病毒的新方法

研究了一种利用新型荧光探针——分子信标进行植物病毒检测的方法，可以不要求对病毒RNA进行严格的分离和纯化，就能快捷地得到检测结果。此方法被用于烟草花叶病毒(tobacco mosaic virus，TMV)基因组RNA的检测，为植物病毒分子生物学的研究提供了新的手段。     

蛋白质分子荧光探针研究及其应用新进展

人体中多达10万种以上的蛋白质结构,功能千差万别,形成了生命的多样性和复杂性。在分子水平上分析和识别蛋白质对生命科学研究具有重要的理论和实践意义。本文综述了各种蛋白质分子荧光探针在蛋白质分析方面的应用,并展望了此类荧光探针的发展趋势和应用前景。引用文献60篇。     

基于联合荧光机制的激发态分子内质子转移荧光探针研究进展

荧光探针能够实现对分析物的快速检测,并因其优异的选择性、高灵敏度和操作简便等优点成为近年的研究热点.激发态分子内质子转移(ESIPT)是最基础的荧光设计策略之一,基于ESIPT原理设计的荧光探针具有发光强度高、Stokes位移大以及反应过程可逆等优点,但也存在对环境敏感、发射波段较短等不足.近年来,将ESIPT与其它荧...     

纳米荧光探针用于核酸分子的检测及成像研究

核酸,包括脱氧核糖核酸和核糖核酸,在生物的生长、发育、突变、炎症、癌症等正常或异常的生命活动中发挥着重要的作用,它们的异常表达与多种疾病的发生、发展也密切相关.因此,发展准确、有效的方法实现核酸分子的检测,对深入探究核酸的功能调控以及相关疾病的早期检测与治疗都具有重要的意义.荧光检测法与荧光成像技术具有灵敏度高、时空分辨率高等优点,为实时、准确的检测核酸分子提供了有力的工具.本文着重综述了近年来发展的纳米荧光探针用于疾病相关核酸分子的检测与细胞和活体成像工作的研究进展,最后提出了进一步构建新型纳米荧光探针用于核酸检测面临的挑战、未来发展方向与展望.     

检测生理内源性一氧化氮分子探针的研究及应用进展

本文介绍和评述了荧光光度法、化学发光法、分光度度法、电化学和电子自旋共振光谱法中的分子探针及在检测生理内源性一氧化氮的应用及研究进展。引用文献42篇。     

分子信标荧光探针用于抑癌基因ING1表达产物的定量测定

根据抑癌基因ING1基因的序列设计并合成了检测ING1转录产物的分子信标核酸探针,发展了一种快速测量从正常细胞系和鼻咽癌肿瘤细胞系提取的ING1转录产物的方法,所得结果与用逆转录结合PCR法(RT-PCR)得到的结果相吻合.并且,将能表达ING1基因的质粒转入肿瘤细胞进行培养后,再将分子信标转入肿瘤细胞,发现转导了质粒的肿瘤细胞比未转导质粒的肿瘤细胞内的荧光明显增强,从而进一步证实了所设计的分子信标核酸探针与ING1转录产物的结合.     

蛋白质标记荧光探针的研究及其进展

蛋白质标记荧光探针在生物分析及蛋白质组学中的应用日益广泛,被用于在分子水平上分析和识别蛋白质,检测蛋白质复杂的构象变化及各项生理活动过程如蛋白质之间的相互作用等.本文评述了近年来该类探针的研究及进展,展望了其应用前景,引用文献63篇.     

荧光分子探针在糖精钠检测中的应用

随着科技的发展和社会的进步,食品安全问题越来越受到关注。糖精钠作为一种食品添加剂,其非法添加事件时有发生,因此,有必要找到一种快速准确检测糖精钠的方法。荧光分子探针因具有灵敏度高、选择性好、响应时间短的优点,其在分析化学检测中的应用越来越广泛。本文设计并合成了一种含蒽荧光团的氮杂15-冠-5化合物,利用分子识别的原理,该目标化合物能够特异性识别溶液中的糖精钠,使溶液的荧光强度发生变化,具有肉眼可见、易于观察的特点,该方法为食品中糖精钠的快速检测提供了一种可行的手段。     

分子信标的构建及其应用研究进展

分子信标(molecular beacon,MB)是一种寡聚核苷酸荧光探针,其具有灵敏度高、特异性强、操作简单以及不必与未反应的探针分离即可实时检测等优点,在分子生物学和基因组学及分子医学等领域具有十分重要的应用价值。本文介绍了近年来出现的各种新型分子信标的结构及工作原理,概述了分子信标技术在生命科学领域中的应用,展望了分子信标技术的发展趋势。     

基于锁核酸的高选择性新型分子信标

通过在分子信标的错配位点修饰锁核酸, 不仅可有效地改善其单碱基错配识别能力, 还可提高检测灵敏度. 因而有望发展成为一种通用的提高分子信标单碱基错配识别能力的方法.     

A Novel Photo‐Induced Electrochemical Biosensing Method Based on Fluorescent Labeled Molecular Beacon

A novel photo‐induced electrochemical biosensing method has been developed based on fluorescence quenching effect and electrochemical method. In this sensing strategy, the molecular beacon probes labeled with methylene blue were immobilized on the gold nanoparticles modified gold electrode surface firstly; then dopamine was assembled on the electrode surface through electrostatic interaction with gold nanoparticles. Under the continuous illumination, the fluorescence of the methylene blue was quenched by the gold nanoparticles before hybridization; after hybridization with the complementary DNA, methylene blue was far away from the gold nanoparticles and the fluorescence recovered, and then singlet oxygen was generated in the photosensitive reaction of methylene blue in the presence of dissolved oxygen. Singlet oxygen reacted with dopamine, which resulted in the reduction of concentration of the dopamine on the electrode surface. The current of the dopamine on the electrode was used for the sensing of the conformational change of molecular beacon and hence for the detection of target DNA.     

分子信标技术

分子信标是一种高灵敏度、高特异性的新型荧光核酸探针。它在与互补DNA／RNA靶序列杂交时放出荧光。本文结合本实验室的研究,从分子信标的结构、性质、应用及发展等进行了介绍。     

A Label-free and Functional Fluorescent Oligonucleotide Probe Based on a G-Quadruplex Molecular Beacon for the Detection of Kanamycin

A label-free and turn-off fluorescent method for the quantitative detection of kanamycin based on a functional molecular beacon was developed. The molecular beacon consists of two hairpin structures with a split G-rich oligonucleotide in the middle. The kanamycin's aptamer formed the loops portion for recognizing kanamycin, and the G-quadruplex bound by Thioflavin T(ThT) was employed as the reporter. In the absence of target, the molecular beacon folded into double stem-loops and the splited G-rich oligonucleotid came close to form a G-quadruplex. When ThT bound to the G-quadruplex, the fluorescence intensity of the solution increased. Upon the addition of kanamycin, the function between kanamycin and aptamer unfolded the hairpin and disassembled the G-quadraplex structure, resulting in a significant decrease in the fluorescence intensity. A good linear relationship ranging from 0.7 nmol/L to 10 nmol/L was achieved and the limit of detection was 0.37 nmol/L. Besides, it could efficiently recognize kanamycin in real samples.     

双偏振干涉测量技术在生物分析方面研究应用进展

双偏振干涉测量(dual-polarization interferometry,DPI)技术是2000年以后出现的一种灵敏、实时、无需标记的新型表面状态分析方法,它能够在亚秒尺度精确测量界面层厚度、密度和质量的绝对值.所以,DPI在固/液界面上蛋白质结构、功能表征,蛋白质之间或与其它分子间的相互作用研究,核酸固定化及杂交检测研究,模拟生物膜研究以及表面超微结构表征等方面都有着广泛的应用.本文介绍了DPI的测量原理和特点,着重评述了近年来DPI在生物分析方面的应用进展.     

Aptamer Molecular Beacon Sensor for Rapid and Sensitive Detection of Ochratoxin A

Ochratoxin A (OTA) is a carcinogenic fungal secondary metabolite which causes wide contamination in a variety of food stuffs and environments and has a high risk to human health. Developing a rapid and sensitive method for OTA detection is highly demanded in food safety, environment monitoring, and quality control. Here, we report a simple molecular aptamer beacon (MAB) sensor for rapid OTA detection. The anti-OTA aptamer has a fluorescein (FAM) labeled at the 5′ end and a black hole quencher (BHQ1) labeled at the 3′ end. The specific binding of OTA induced a conformational transition of the aptamer from a random coil to a duplex–quadruplex structure, which brought FAM and BHQ1 into spatial proximity causing fluorescence quenching. Under the optimized conditions, this aptamer sensor enabled OTA detection in a wide dynamic concentration range from 3.9 nM to 500 nM, and the detection limit was about 3.9 nM OTA. This method was selective for OTA detection and allowed to detect OTA spiked in diluted liquor and corn flour extraction samples, showing the capability for OTA analysis in practical applications.     

脱氧核糖核酸电分析化学研究进展

就DNA电分析化学研究及其应用方面进行综述，主要叙述了DNA的各种电分析化学方法，以及DNA电化学传感器的原理，应用以及发展，本文引用文献77篇。     

Label-Free Fluorescence Molecular Beacon Probes Based on G-Triplex DNA and Thioflavin T for Protein Detection

Protein detection plays an important role in biological and biomedical sciences. The immunoassay based on fluorescence labeling has good specificity but a high labeling cost. Herein, on the basis of G-triplex molecular beacon (G3MB) and thioflavin T (ThT), we developed a simple and label-free biosensor for protein detection. The biotin and streptavidin were used as model enzymes. In the presence of target streptavidin (SA), the streptavidin hybridized with G3MB-b (biotin-linked-G-triplex molecular beacon) perfectly and formed larger steric hindrance, which hindered the hydrolysis of probes by exonuclease III (Exo III). In the absence of target streptavidin, the exonuclease III successively cleaved the stem of G3MB-b and released the G-rich sequences which self-assembled into a G-triplex and subsequently activated the fluorescence signal of thioflavin T. Compared with the traditional G-quadruplex molecular beacon (G4MB), the G3MB only needed a lower dosage of exonuclease III and a shorter reaction time to reach the optimal detection performance, because the concise sequence of G-triplex was good for the molecular beacon design. Moreover, fluorescence experiment results exhibited that the G3MB-b had good sensitivity and specificity for streptavidin detection. The developed label-free biosensor provides a valuable and general platform for protein detection.