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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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基于上转换荧光纳米粒子和金纳米粒子间荧光共振能量转移的高灵敏赭曲霉毒素A检测方法研究 总被引:1,自引:0,他引:1
制备了水溶性的上转换荧光纳米材料,在其表面修饰赭曲霉毒素A(OTA)适配体作为能量供体探针;在金纳米粒子表面修饰OTA适配体互补链作为能量受体探针,构建了OTA适配体传感器。在最优条件下,OTA的检测范围为0.001~10 ng/mL,检出限可达0.001 ng/mL。将其应用于啤酒样品中OTA的检测,当加标水平为0.01、0.1、1.0 ng/mL时,回收率为100%~119%,相对标准偏差为4.3%~4.9%,表明该方法可用于实际样品检测。该方法具有灵敏度高、特异性好、操作简单、成本较低等优点。 相似文献
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利用壳聚糖(CS)、还原氧化石墨烯(rGO)与氮掺杂多壁碳纳米管(N-MWCNTs)合成N-MWCNTs-rGO-CS复合材料,制备修饰电极,结合赭曲霉毒素A(OTA)的特异性适配体,构建高灵敏度电化学生物传感器,并用于中药中OTA的含量测定。在最优条件下,峰电流变化值与OTA浓度对数值的线性响应范围为2.3 pmol/L~2.3 nmol/L,检测限为0.53 pmol/L。应用该方法对中药饮片中OTA的含量进行加标回收实验,回收率在97.6%~103.2%之间。该方法有望用于中药材中OTA污染的快速检测。 相似文献
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赭曲霉毒素A(OTA)是由曲霉和青霉产生的一种真菌毒素,具有强烈的肝肾毒性,并有致畸、致癌的危害。OTA广泛存在于如小麦、玉米、咖啡、葡萄等谷物及食品中,严重危害人类健康。鉴于其危害的严重性和分布的广泛性,发展方便快捷、高灵敏度的OTA检测技术具有重要意义。目前检测OTA的方法有薄层色谱法、高效液相色谱法、荧光分析法及酶联免疫吸附测定法等,这些方法通常成本高、操作复杂且费时。光学适配体传感器发展迅速,在OTA检测领域表现出巨大优势,因此综述了荧光型(包括标记型和免标记型)、比色型、化学发光型以及其他类型(表面等离子体共振、侧向层析、表面增强拉曼散射型)光学适配体传感器检测OTA的原理、性能及在2011-2023年间的相关应用,并对方法面临的问题进行了总结以及未来的的发展趋势进行了展望(引用文献81篇)。 相似文献
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赭曲霉素A(OTA)是污染中药材的重要真菌毒素,严重影响中药材质量和用药安全.在小檗碱溶液中加入OTA和其核酸适配体后,处于随意卷曲状态的核酸适配体会被OTA诱导折叠成为G-四链体构象,使小檗碱的微环境发生改变,从而增强其荧光信号.基于此,本文以OTA核酸适配体为识别原件,小檗碱为荧光探针发展了一种无标记的荧光体系检测OTA.对主要影响因素,包括K+,Mg2,小檗碱和核酸适配体浓度进行了优化.在最佳实验条件下,小檗碱荧光信号变化值与OTA浓度在5~200 nmol/L范围内成正比,检出限5 nmol/L.该方法仅使用无标记的核酸适配体完成了OTA的检测,避免了对核酸适配体的繁琐设计和标记.方法 有较高的特异性,并成功应用于中药桔梗中OTA的检测,回收率在86.3%~105.6%之间. 相似文献
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赭曲霉毒素A(Ochratoxin A,OTA)是一种由赭曲霉、青霉菌等真菌产生的次级代谢产物,在自然界分布广泛,具有肝毒性、肾毒性、致癌、致突变作用。鉴于其危害的严重性和污染的广泛性,发展高灵敏度的OTA检测技术引起了研究者的广泛关注。该文阐述了近年来新型电化学传感技术在OTA 检测方面的发展及应用,全面综述了目前OTA电化学传感器的主要类型及其优缺点,并对其发展方向提出了展望,从而为基于OTA的电化学传感器的深入研究与应用提供了参考。 相似文献
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以赭曲霉毒素A(OTA)为目标物,以二氧化硅纳米颗粒作为载体,负载赭曲霉毒素适配体和HCR引发链(cDNA)杂交的DNA双链,构建了一种比色/荧光双模信号输出的高灵敏检测平台。在最优条件下,荧光信号回归方程为ΔF=1033.78lgc+13652.89,检出限为6.11×10-14 g/mL;比色信号回归方程为A=0.02587lgc+0.7537,检出限为1.33×10-13 g/mL。该方法成功应用于实际样品中OTA的检测,为食品安全监测提供了一种新策略。 相似文献
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Aptamer-based biosensors for the detection of HIV-1 Tat protein 总被引:7,自引:0,他引:7
Tombelli S Minunni M Luzi E Mascini M 《Bioelectrochemistry (Amsterdam, Netherlands)》2005,67(2):135-141
Two biosensors have been constructed using an RNA aptamer as biorecognition element. The aptamer, specific for HIV-1 Tat protein, has been immobilised on the gold surface of piezoelectric quartz crystals or surface plasmon resonance (SPR) chips to develop a quartz crystal microbalance (QCM)-based and an SPR-based biosensor, respectively. Both the biosensors were modified with the same immobilisation chemistry based on the binding of a biotinylated aptamer on a layer of streptavidin. The binding between the immobilised aptamer and its specific protein has been evaluated with the two biosensors in terms of sensitivity, reproducibility and selectivity. A protein very similar to Tat, Rev protein, has been used as negative control. The two biosensors both were very reproducible in the immobilisation and the binding steps. The selectivity was high in both cases. 相似文献
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We explored a fluorescent strategy for sensing ochratoxin A (OTA) by using a single fluorophore-labeled aptamer for detection of OTA. This method relied on the change of the fluorescence intensity of the labeled dye induced by the specific binding of the fluorescent aptamer to OTA. Different fluorescein labeling sites of aptamers were screened, including the internal thymine bases, 3′-end, and 5′-end of the aptamer, and the effect of the labeling on the aptamer affinity was investigated. Some fluorophore-labeled aptamers showed a signal-on or signal-off response. With the fluorescent aptamer switch, simple, rapid, and selective sensing of OTA at nanomolar concentrations was achieved. OTA spiked in diluted red wine could be detected, showing the feasibility of the fluorescent aptamer for a complex matrix. This method shows potential for designing aptamer sensors for other targets. Figure
A simple fluorescent approach for OTA sensing is achieved by using single fluorophore-labeled aptamer. A fluorophore is attached on one site of the aptamer. The affinity binding of OTA induces the alteration of fluorescence properties of the labeled fluorophore as the consequence of the conformation change of the aptamer. OTA can be detected by measuring the change of fluorescence signals of the labeled dye 相似文献
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Xia Geng Dapeng Zhang Hailin Wang Qiang Zhao 《Analytical and bioanalytical chemistry》2013,405(8):2443-2449
By taking advantage of the intrinsic fluorescence of ochratoxin A (OTA), we present a fluorescence anisotropy approach for rapid analysis of the interactions between OTA and aptamers. The specific binding of OTA with a 36-mer aptamer can induce increased fluorescence anisotropy (FA) of OTA as the result of the freedom restriction of OTA and the increase of molecular volume, and the maximum FA change is about 0.160. This FA approach enables an easy way to investigate the effects of buffer compositions like metal ions on the affinity binding. FA analysis shows the interaction between OTA and aptamer is greatly enhanced by the simultaneous presence of Ca2+ and Na+, while the binding affinity of aptamer decreases more than 18-fold when only Ca2+ exists, and the binding is completely lost when Ca2+ is absent. Crucial region of the aptamer for binding can be mapped through FA analysis and aptamer mutation. The demonstrated FA approach maintains the advantages of FA in simplicity, rapidity, and robustness. This investigation will help the development of aptamer-based assays for OTA detection in optimizing the binding conditions, modification of aptamers, and rational design. Figure
The free ochratoxin A (OTA) molecule tumbles rapidly and shows low fluorescence anisotropy (FA), while the bound OTA by the aptamer has increased molecular volume and restricted freedom, showing enhanced FA. FA analysis allows screening the interaction between OTA and aptamer 相似文献
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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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In this study, we for the first time presented an efficient, accurate, rapid, simple and ultrasensitive detection system for small molecule ochratoxin A (OTA) by using the integration of loop-mediated isothermal amplification (LAMP) technique and subsequently direct readout of LAMP amplicons with a signal-on electrochemiluminescent (ECL) system. Firstly, the dsDNA composed by OTA aptamer and its capture DNA were immobilized on the electrode. After the target recognition, the OTA aptamer bond with target OTA and subsequently left off the electrode, which effectively decreased the immobilization amount of OTA aptamer on electrode. Then, the remaining OTA aptamers on the electrode served as inner primer to initiate the LAMP reaction. Interestingly, the LAMP amplification was detected by monitoring the intercalation of DNA-binding Ru(phen)32+ ECL indictors into newly formed amplicons with a set of integrated electrodes. The ECL indictor Ru(phen)32+ binding to amplicons caused the reduction of the ECL intensity due to the slow diffusion of Ru(phen)32+–amplicons complex to the electrode surface. Therefore, the presence of more OTA was expected to lead to the release of more OTA aptamer, which meant less OTA aptamer remained on electrode for producing LAMP amplicons, resulting in less Ru(phen)32+ interlaced into the formed amplicons within a fixed Ru(phen)32+ amount with an obviously increased ECL signal input. As a result, a detection limit as low as 10 fM for OTA was achieved. The aptasensor also has good reproducibility and stability. 相似文献
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Alonso-Lomillo MA Domínguez-Renedo O Román Ldel T Arcos-Martínez MJ 《Analytica chimica acta》2011,(1):49-53
This work summarizes the manufacturing procedure of Horseradish peroxidase (HRP) based biosensors for the determination of the mycotoxin Ochratoxin A (OTA). The biosensors have been fabricated using the single technology of screen-printing. That is to say, an HRP containing ink has been directly screen-printed onto carbon electrodes, which offers a higher rapidity and simplicity in the manufacturing process of biosensors for OTA determination. The formal redox potential of the Fe(III/II) moiety of HRP has been used to demonstrate the effective loading of enzyme into the ink. The chronoamperometric oxidation current registered has been successfully related to the concentration of OTA in solution from different samples, including beer ones. Under the optimum conditions of the experimental variables, precision in terms of reproducibility and repeatability has been calculated in the concentration range from 23.85 to 203.28 nM. A relative standard deviation for the slopes of 10% (n = 4) was obtained for reproducibility. In the case of repeatability, the biosensor retained a 30% of the initial sensitivity after the third calibration. The average capability of detection for 0.05% probabilities of false positive and negative was 26.77 ± 3.61 nM (α = 0.05 and β = 0.05, n = 3). 相似文献