Dengue virus (DENV) is one of the most important mosquito-borne viruses in tropical and subtropical regions. Development of severe forms of dengue viral infection such as dengue fever (DF) and dengue hemorrhagic fever (DHF) has claimed many lives. The standard methods for detecting dengue virus are time consuming, laborious, and require skilful personnel. In this study, we propose a method whereby DENV RNA extracted from dengue infected mosquitoes was converted into DNA for probe hybridization to generate silver nanocluster strands that could be visualised under UV light. Label-free silver nanocluster based DNA sensors are able to provide strong fluorescence upon DNA hybridization. Highly specific DNA sequence detection is possible by taking advantage of the specificity of DNA hybridization kinetics. The proposed system is capable of detecting all four dengue DNA serotypes (DENV1–4) without any cross-reactivity. A single tube assay format showed better hybridisation efficiency with higher fluorescence intensity generated and a lower detection limit compared to a cocktail probe assay format. The method was able to detect as low as 100 nM of amplified double stranded dengue DNA targets using both single and cocktail probe assays. This provides an interesting alternative approach for multiplex DNA sensing utilizing DNA silver nanoclusters as a reporter system.

中文翻译：

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使用无标记DNA传感器进行登革热血清分型†

登革热病毒（DENV）是热带和亚热带地区最重要的蚊媒病毒之一。登革热（DF）和登革出血热（DHF）等严重形式的登革热病毒感染的发展夺走了许多生命。检测登革热病毒的标准方法耗时，费力并且需要熟练的人员。在这项研究中，我们提出了一种方法，该方法将从登革热感染的蚊子中提取的DENV RNA转换成DNA以进行探针杂交，以生成可在紫外光下可视化的银纳米簇链。基于无标记的银纳米簇的DNA传感器能够在DNA杂交后提供强荧光。通过利用DNA杂交动力学的特异性，可以进行高度特异性的DNA序列检测。拟议的系统能够检测所有四种登革热DNA血清型（DENV1-4），而无任何交叉反应。与鸡尾酒探针测定法形式相比，单管测定法形式显示出更好的杂交效率，产生了更高的荧光强度和更低的检测限。使用单探针法和鸡尾酒探针法，该方法都能检测到低至100 nM的扩增的双链登革热DNA靶标。这提供了一种有趣的替代方法，可利用DNA银纳米团簇作为报告系统对DNA进行多重感测。使用单探针法和鸡尾酒探针法，该方法都能检测到低至100 nM的扩增的双链登革热DNA靶标。这提供了一种有趣的替代方法，可利用DNA银纳米团簇作为报告系统对DNA进行多重感测。使用单探针法和鸡尾酒探针法，该方法都能检测到低至100 nM的扩增的双链登革热DNA靶标。这提供了一种有趣的替代方法，可利用DNA银纳米团簇作为报告系统对DNA进行多重感测。