Adegoke Oluwasesan, Park Enoch Y
Laboratory of Biotechnology, Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka 422-8529, Japan.
J Mater Chem B. 2017 Apr 28;5(16):3047-3058. doi: 10.1039/c7tb00388a. Epub 2017 Apr 11.
Novel probes that can accurately (with sensitivity and specificity) detect and discriminate between the various serotypes of dengue virus (DENV) are needed for point-of-care treatment. The efficacy of a fluorophore reporter at optically transducing an ultrasensitive fluorescence intensity signal for a target nucleic acid within a molecular beacon (MB) biosensor system depends primarily on its optical properties. A new class of bright luminescent and size-dependent glutathione (GSH)-functionalized CdSe/ZnSeS core/alloyed shell quantum dots (Qdots) have been synthesized and characterized. Shell alloying tuned the photoluminescence (PL) quantum yield within the range of 23-99%, representing an approximately 2-8-fold increase over that of the binary CdSe core. In the first step of the biosensor design, gold nanoparticles (AuNPs) were conjugated to the Qdots to form AuNP-Qdot nanohybrids. In the second step, the AuNP-Qdot nanohybrids were conjugated to the 5' end of the MB. Despite the strong binding of the entities, both the AuNP-Qdot and AuNP-Qdot-MB conjugates maintained high colloidal stability. Nucleic acids of DENV1-4 were detected by the AuNP-Qdot-MB biosensors with high sensitivity, with the detection limits of the serotypes ranging from 31-260 copies per mL. The biosensor specifically discriminated between each serotype of the virus. A sensitivity comparison of a Qdot-MB with the AuNP-Qdot-MB showed that the localized surface plasmon resonance-induced signal from the AuNPs to the fluorescence intensity of the Qdots enhanced the performance of the biosensor. We have developed a new AuNP-Qdot-MB biosensor for DENV possessing high sensitivity and specificity. The new ultrasensitive assay holds great promise for the specific diagnosis of DENV, while the versatile biosensor concept is applicable to any type of RNA virus.
即时护理治疗需要能够准确（具有敏感性和特异性）检测并区分登革热病毒（DENV）各种血清型的新型探针。在分子信标（MB）生物传感器系统中，荧光团报告分子将超灵敏荧光强度信号光学转换为目标核酸的效率主要取决于其光学性质。一类新型的明亮发光且尺寸依赖的谷胱甘肽（GSH）功能化CdSe/ZnSeS核/合金壳量子点（Qdots）已被合成并表征。壳层合金化将光致发光（PL）量子产率调节在23%至99%的范围内，比二元CdSe核提高了约2至8倍。在生物传感器设计的第一步，金纳米颗粒（AuNPs）与量子点共轭形成AuNP-Qdot纳米杂化物。在第二步中，AuNP-Qdot纳米杂化物与MB的5'端共轭。尽管各实体之间结合紧密，但AuNP-Qdot和AuNP-Qdot-MB共轭物均保持了高胶体稳定性。AuNP-Qdot-MB生物传感器以高灵敏度检测了DENV1-4的核酸，各血清型的检测限为每毫升31至260个拷贝。该生物传感器能特异性区分病毒的每种血清型。Qdot-MB与AuNP-Qdot-MB的灵敏度比较表明，AuNPs的局域表面等离子体共振诱导信号到量子点荧光强度的增强提高了生物传感器的性能。我们开发了一种用于DENV的新型AuNP-Qdot-MB生物传感器，具有高灵敏度和特异性。这种新型超灵敏检测方法在DENV的特异性诊断方面极具前景，而这种通用的生物传感器概念适用于任何类型的RNA病毒。
