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适配体是通过指数富集系统进化技术(SELEX)体外筛选得到的一类能够特异性地结合小分子物质、蛋白,甚至整个细胞的寡核苷酸序列.由于具有制备简便、易于修饰、稳定性好等特点,适配体已广泛应用于构建生物传感器,实现对病原微生物的识别和检测.本文在阐述适配体基本原理的基础之上,结合近年来病原微生物适配体研究领域的最新研究成果,综述以病原微生物为目标的适配体筛选技术的最新进展;列举目前已经筛选获得的病原微生物(原生生物、病毒、细菌)适配体;综述适配体生物传感器在病原微生物检测中的应用.并展望了适配体生物传感器在病原微生物检测领域的发展趋势. 相似文献
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韩冰贾永梅李志果周国华刘培炼余彪张玲玲薛茗月 《分析科学学报》2022,(3):371-376
核酸适配体作为一种新型识别分子,具有亲和力高、稳定性强、制备成本低、特异性强等优点,但其自身不具有信号转换功能,它与靶标分子特异性结合过程,不可产生被检测的物理化学信号。因此,需将核酸适配体与靶标分子特异性识别结合过程转为易于被检测的物理化学信号变化的过程。根据信号转换方式的不同,可将适配体生物传感器分为荧光适配体传感器、比色适配体传感器、电化学适配体传感器和表面拉曼散射适配体传感器。本文对基于以上4种检测信号的核酸适配体生物传感器在黄曲霉毒素(AFB1)检测方面的应用进行综述,并概述该类传感器应用前景和当前面临的挑战。 相似文献
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以特异性识别凝血酶的适配体为分子识别物质,以氨基钌联吡啶衍生物(Ru1)为电化学发光信号物质,基于吡咯/N-(2-羧乙基)吡咯纳米粒子(Ppy-pa NPs)负载适配体和Ru1研制了一种高灵敏检测凝血酶的电化学发光适配体传感器.以N-(2-羧乙基)吡咯和吡咯为单体,采用微乳液聚合方法制备了Ppy-pa NPs.通过EDC/NHS将Ru1与Ppy-pa NPs表面的羧基共价连接制备了Ru1功能化Ppy-pa NPs(Ru1-Ppy-pa NPs).利用核磁共振图谱、傅里叶变换红外光谱和投射电子显微镜图对Ppy-pa NPs和Ru1-Ppy-pa NPs进行了表征.将Ppy-pa NPs Nafion混合物滴涂在石墨电极表面制备成电化学发光化学传感器,可高灵敏检测三丙胺(检出限为3.0×10-8M).通过电化学氧化将对氨基苯磺酸共价键合在石墨电极表面,将5′修饰氨基凝血酶适配体I(TBA-I)共价连接在对氨基苯磺酸修饰的石墨电极表面制备成电化学发光适配体传感器.将5′修饰氨基凝血酶适配体Ⅱ(TBA-Ⅱ)标记在Ru1-Ppy-pa NPs表面制得电化学发光适配体信号探针(Ppy-pa NPs-Ru1-TBA-II).当凝血酶存在时,凝血酶与电极表面的TBA-I特异性结合,再与信号探针结合形成夹心结构,产生很强的电化学发光信号.该传感器具有极低的检出限(3.0×10-16M)和良好的选择性.本工作表明以Ppy-pa NPs为电化学光探针的载体可构建高灵敏度和选择性的电化学发光生物传感器. 相似文献
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核酸适配体因能与目标物特异性结合而被用作生物识别元件,广泛用于生物传感器的研究。基于适配体的比色生物传感器,因简便、经济且直观可视等特点,在环境保护、医疗诊断和食品安全等领域备受青睐。随着生物技术和纳米技术的迅速发展,结合不同显色途径和信号放大方法,已建立了多种操作简便、特异性强、灵敏度高的基于适配体的比色传感方法,为现场快速检测技术的发展提供了新思路和新选择。识别元件、信号探针及信号放大策略都是影响比色生物传感器准确性和灵敏度的重要因素,纳米材料和放大策略的选择及设计非常重要。本文主要基于酶催化和等离子体共振比色原理,介绍了近年来比色适配体传感器的研究进展,为高灵敏比色生物传感器的研究和应用提供参考。 相似文献
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赭曲霉毒素(Ochratoxin)是一类主要由曲霉菌和青霉菌产生的次生代谢产物,其中赭曲霉毒素A(OTA)的毒性最强。OTA相当稳定,常规的食品加工难以去除,若摄入受OTA污染的食品或药物会对人类造成严重的危害。实现对OTA的灵敏和快速检测是及早发现和处置OTA污染的关键。近年来,核酸适配体因其独特的优点,被作为抗体的替代物用于构建OTA电化学生物传感器。本文介绍了经典的OTA检测方法和基于适配体的电化学生物传感检测方法,从OTA电化学适配体传感器的适配体优化、新型材料应用以及生物信号放大技术的应用等三个方面总结了该生物传感技术的研究现状,并对其未来的发展进行了展望。 相似文献
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Hu Fu Chuang Ge Wei Cheng Caihui Luo Decai Zhang Li Yan Yun He Gang Yi 《Electroanalysis》2013,25(5):1223-1229
An electrochemical aptasensor was developed for sensitive and specific detection of thrombin by combining homogenous recognition strategy and gold nanoparticles (AuNPs) amplification. Streptavidin‐alkaline phosphatase was used as reporter molecule. Compared with the traditional hairpin aptasensor monitoring the distance of the redox molecule from the electrode surface, the proposed aptasensor successfully overcome the limitations of distance and improved the stability and high affinity of the aptamer hairpin through homogenous recognition, which enhanced the sensitivity and selectivity of the sensors effectively. Additionally, AuNPs were employed to increase the active area and conductivity of the electrode, thus, improving the sensitivity of the aptasensor. As a result, the designed thrombin detection sensor obtained a lower detection limit of 0.52 pM in buffer and 6.9 pM in blood serum. 相似文献
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This article describes a simple and homogeneous fluorescent aptasensor for the detection of ochratoxin A (OTA). With its high specificity and simplicity; RecJf exonuclease is used to cleave DNA strand of the FAM-aptamer/OTA complex and realize target recycling signal amplification. In order to avoid the loss of reaction system, magnetic beads (MBs) are added only once at the last experimental step. This proposed fluorescent aptasensor showed the higher sensitivity in the range of 0.1–100 ng/mL with LOD of 0.056 ng/mL, and the good selectivity against other interfering toxins. The feasibility of the prepared aptasensor was studied by detecting OTA in spiked liquor and cereal samples. The obtained average recoveries ranged from 92% to 115%. This study provides a promising application with convenience and rapidness in the aptasensor fabrication for food safety analysis. 相似文献
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Electronic aptamer-based sensors 总被引:4,自引:0,他引:4
The selection of aptamers-nucleic acids that specifically bind low-molecular-weight substrates or proteins-by the SELEX (systematic evolution of ligands by exponential enrichment) procedure has attracted recent efforts directed to the development of new specific recognition units. In particular, extensive activities have been directed to the application of aptamers as versatile materials for the design of biosensors. The Minireview summarizes the recent accomplishments in developing electronic aptamer-based sensors (aptasensors), which include electrochemical, field-effect transistor, and microgravimetric quartz crystal microbalance sensors, and describes methods to develop amplified aptasensor devices and label-free aptasensors. 相似文献
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Jing-Jing Liu Xiao-Rong SongYi-Wei Wang Ai-Xian ZhengGuo-Nan Chen Huang-Hao Yang 《Analytica chimica acta》2012
A simple turn-on and homogeneous aptasensor, which relies on target induced formation of silver nanoclusters (Ag NCs), was developed for the determination of platelet-derived growth factor B-chain homodimer (PDGF-BB). The aptasensor contains two hairpin DNA probes termed as P1 and P2. P1 consists of the aptamer sequence of PDGF-BB. Meanwhile, P2 contains the Ag NCs nucleation sequence, which is blocked by the hairpin stem region. P1 and P2 can co-exist metastably in the absence of PDGF-BB and maintain hairpin structure. However, in the presence of PDGF-BB, the binding of PDGF-BB with aptamer will result in the hybridization between P1 and P2, and release the Ag NCs nucleation sequence. In this case, Ag NCs can be formed via the reduction of Ag+ by NaBH4. By monitoring the increase in fluorescence intensity, we could detect the target protein with high sensitivity. The detection limit of this aptasensor is 0.37 nM, which is comparable with that of other reported aptasensors. Furthermore, this proposed aptasensor shows high selectivity toward its target protein. Thus, the proposed aptasensor based on target induced formation of Ag NCs could be used as a sensitive and selective platform for the detection of target protein. 相似文献
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《Arabian Journal of Chemistry》2022,15(9):104067
Sulfadiazine (SDZ) is a broad-spectrum antibiotic used to treat bacterial infections in animals, and SDZ residues in food can be harmful to human health. As a result, an aptasensor based on silica nanoparticles was developed for the rapid detection of SDZ. An aptamer that specifically binds to SDZ was obtained using graphene oxide-SELEX and further truncated to a 13 nt sequence (SDZ30-1:5′-AACCCAATGGGAT-3′), which has a high affinity (Kd = 65.72 nM). In addition, it was found by molecular simulation that a steric hindrance could prevent the target molecule from entering the binding pocket formed by the key base “TGG”, which affects the total binding free energy of SDZ30-1 and the target molecule, thereby affecting the affinity of SDZ30-1 to the target. The SDZ30-1 was selected as the fluorescent probe to establish an aptasensor for the detection of SDZ residues in milk and honey. The aptasensor exhibited a wide dynamic linear range (3.125 – 100 ng/mL) and a limit of detection (LOD = 1.68 ng/mL). The aptasensor in spiked samples recovered at a rate of 95.12 – 105.47%, with a coefficient of variation of less than 13.18 %. The results of aptasensor were positively correlated with those of HPLC (R2 > 0.8687). Based on the above results, it could be inferred that the aptasensor can be used sensitively and rapidly for the detection of SDZ residues in edible tissue. 相似文献
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In this communication, we develop a novel fluorescent aptasensor for thrombin detection with the use of poly(m-phenylenediamine) (PMPD) rods as an effective sensing platform. This aptasensor exhibits extraordinarily high sensitivity with a detection limit as low as 100 pM and excellent selectivity. 相似文献
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以电活性钌化合物[Ru(NH3)6]3+为信号传感源,借助碳纳米管构建了高灵敏检测腺苷免标记电化学传感电极(BSA/Apt/CNTs/GC). BSA/Apt/CNTs/GC电极在最佳实验条件下检测腺苷线性范围为5.0×10-11 ~ 1.0×10-7 mol·L-1,检测下限为2.7×10-11 mol·L-1. 该传感电极有较高的灵敏度、良好的选择性、重现性和稳定性. 与传统标记型适体传感电极相比,其制作简便,也许还适用于其他小分子和蛋白质的检测,有一定的普适性. 相似文献
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Zheng AX Wang JR Li J Song XR Chen GN Yang HH 《Chemical communications (Cambridge, England)》2012,48(3):374-376
A simple and highly sensitive homogeneous aptasensor is developed, which relies on nicking enzyme. The sensitivity of this newly proposed aptasensor is about three orders of magnitude higher than that of traditional homogeneous aptasensors. Furthermore, it is capable of detecting target protein in real samples. 相似文献
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Nawel Mejri-Omrani Anna Miodek Becem Zribi Mouna Marrakchi Moktar Hamdi Jean-Louis Marty Hafsa Korri-Youssoufi 《Analytica chimica acta》2016
Ochratoxin A (OTA) is a carcinogenic mycotoxin that contaminates food such as cereals, wine and beer; therefore it represents a risk for human health. Consequently, the allowed concentration of OTA in food is regulated by governmental organizations and its detection is of major agronomical interest. In the current study we report the development of an electrochemical aptasensor able to directly detect trace OTA without any amplification procedure. This aptasensor was constructed by coating the surface of a gold electrode with a film layer of modified polypyrrole (PPy), which was thereafter covalently bound to polyamidoamine dendrimers of the fourth generation (PAMAM G4). Finally, DNA aptamers that specifically binds OTA were covalently bound to the PAMAM G4 providing the aptasensor, which was characterized by using both Atomic Force Microscopy (AFM) and Surface Plasmon Resonance (SPR) techniques. The study of OTA detection by the constructed electrochemical aptasensor was performed using Electrochemical Impedance Spectroscopy (EIS) and revealed that the presence of OTA led to the modification of the electrical properties of the PPy layer. These modifications could be assigned to conformational changes in the folding of the aptamers upon specific binding of OTA. The aptasensor had a dynamic range of up to 5 μg L−1 of OTA and a detection limit of 2 ng L−1 of OTA, which is below the OTA concentration allowed in food by the European regulations. The efficient detection of OTA by this electrochemical aptasensor provides an unforeseen platform that could be used for the detection of various small molecules through specific aptamer association. 相似文献
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Jing Yang Wei Zhong Qi Yu Jin Zou Yansha Gao Shuwu Liu Songbai Zhang Xiaoqiang Wang Limin Lu 《Molecules (Basel, Switzerland)》2022,27(6)
A simple and label-free electrochemical aptasensor was developed for ultra-sensitive determination of chloramphenicol (CAP) based on a 2D transition of metal carbides (MXene) loaded with gold nanoparticles (AuNPs). The embedded AuNPs not only inhibit the aggregation of MXene sheets, but also improve the quantity of active sites and electronic conductivity. The aptamers (Apts) were able to immobilize on the MXene–AuNP modified electrode surface through Au–S interaction. Upon specifically binding with CAP with high affinity, the CAP–Apt complexes produced low conductivity on the aptasensor surface, leading to a decreased electrochemical signal. The resulting current change was quantitatively correlated with CAP concentration. Under optimized experimental conditions, the constructed aptasensor exhibited a good linear relationship within a wide range of 0.0001–10 nM and with a low detection limit of 0.03 pM for CAP. Moreover, the developed aptasensor has been applied to the determination of CAP concentration in honey samples with satisfactory results. 相似文献