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《Electroanalysis》2017,29(5):1310-1315
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. 相似文献
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针对移动信标光跟踪系统的高精度和高稳定性的要求,设计了移动信标光跟踪仿真系统。采用双DSP和两轴精密转台搭建了粗跟踪的硬件平台。采用中值滤波来消除光斑图像的噪声干扰,质心算法实现对光斑位置的精确提取。采用仿人智能PID控制来改善系统动态跟踪性能,增强了系统对不确定因素的适应性。进行了模拟仿真台运动下的二维动态跟踪实验,实验结果表明跟踪系统有较好的跟踪精度。 相似文献
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Jafar Ezzati Nazhad DolatabadiOmid Mashinchian Baharak AyoubiAli Akbar Jamali Ahmad MobedDusan Losic Yadollah Omidi Miguel de la Guardia 《Trends in analytical chemistry : TRAC》2011,30(3):459-472
In the past two decades, nanoscale advanced materials have been explored for biosensing molecules, so new horizons have opened up for identifying and quantifying biomolecules, and possible early diagnosis of diseases.DNA nanobiosensors show promise. This article provides an overview on their optical and electrochemical aspects. We discuss recent progress in this field, describing basic concepts of molecular beacons and quantum dots as optical nano-imaging systems. Also, carbon nanotubes provide a platform for development and advancement of electrochemical DNA nanobiosensors, which are increasingly being implemented as robust tools for detection in biomedical sciences. 相似文献
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Dr. Debabrata Maity Dr. Khaleel I. Assaf Wilhelm Sicking Dr. Christoph Hirschhäuser Prof. Dr. Werner M. Nau Prof. Dr. Carsten Schmuck 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(57):13088-13093
A convenient supramolecular strategy for constructing a ratiometric fluorescent chemosensing ensemble, consisting of a macrocyclic host (cucurbit[8]uril CB[8]), and a pyrene-tagged amphiphilic peptide beacon (AP 1), is reported. AP 1 unfolds upon encapsulation of the pyrene termini into the hydrophobic CB[8] cavity. This changes pyrene excimer to monomer emission. Substrates with higher affinity for the CB[8] cavity can displace AP 1 from the ensemble. The released AP 1 folds again to form a pyrene excimer, which allows for the ratiometric fluorescence monitoring of the substrate. In this report, the ensemble capacity for ratiometric fluorescence monitoring of biological substrates, such as amino acid derivatives, specific peptides, and proteins, in aqueous media is demonstrated. 相似文献
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Neighbor discovery enables nodes in the networks to discover each other through simple information interaction,which was suitable for the new mobile low duty cycle sensor network (MLDC-WSN).However,because the nodes in MLDC-WSN can move randomly and sleep,the network topology was changed frequently,which results in that some nodes need a lot of energy and time to find their neighbors.How to realize fast neighbor discovery for all nodes in the network was a difficult problem in current research.To solve this problem,a new low-latency neighbor discovery algorithm based on multi-beacon messages was proposed.In this algorithm,the nodes were discovered by sending a short beacon message through their neighbor nodes,and by adjusting the time and frequency of beacon message sent,a lower neighbor discovery delay was obtained.Eventually,through quantitative analysis and simulation experiments,it is found that compared with existing algorithms,this algorithm can find all neighbor nodes in MLDC-WSN with less energy consumption,lower latency and greater probability. 相似文献
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