Molecularly Imprinted Heavy Metal-free Quantum Dots as Fluorescent Probes for Rapid and Accurate Detection of Viruses

最近，新出现的病毒，如SARS-COV-2、寨卡病毒、猴痘和新型流感毒株，明显表明了新病毒感染的风险。需要及早和准确地发现病毒感染，以便进行适当治疗并防止严重的健康并发症。目前的测试，如实时聚合酶链反应，需要很长时间（约1-2天），价格昂贵（约42英镑），需要高技能的人员。抗原检测（如Covid-19侧流检测）提供快速（15-30分钟）和便携式分析；然而，它们的灵敏度水平要低得多，对于某些应用可能还不够。该项目的目的是开发一种足够快速和准确的设备，使卫生专业人员能够诊断病毒性疾病，并在适当情况下为患者提供最适当的治疗和/或尽可能快地隔离他们。本研究将利用半导体量子点（QD）纳米晶体和分子印迹聚合物（MIP）组成荧光探针来检测唾液中的病毒样本。我们的目标是通过利用量子点的独特性质来实现这一目标：在溶液中的单分散，高表面积体积比，稳定的荧光结合测量，高荧光量子产率（90-100%），以及尺寸和形状相关的性质。我们将合成不含镉的无毒量子点，并对其表面进行修饰，使其具有水溶性、致密性和稳定性。我们将它们连接到特异性结合病毒颗粒的mip上。mip通常被称为“塑性”抗体，可以牢固而稳定地与目标结合。一旦病毒颗粒接触到QDs-MIP，它们就会与MIP结合，这将导致QDs通过为被检测的病毒产生独特的荧光信号来翻译结合相互作用。这些量子点将是理想的平台，如纸条和横向流动设备。我们的目标是将它们用于微流控纸分析装置的原型中。这将涉及在纸质设备上创建微流体通道，并将QDs-MIP探针绑定到纸张表面，以便通过肉眼荧光检测病毒。所提出概念的多功能性和敏捷性将确保传感器可以快速修改，以应对任何潜在的未来突变或由其他感染性病原体引起的新爆发。

Recently, the risks from new viral infections have been made evident by emerging viruses such as SARS-COV-2, Zika virus, monkeypox and new strains of influenza. Viral infections need to be detected early and accurately to allow appropriate treatment and prevent serious health complications. Current tests such as real-time polymerase chain reaction takes a long time (~1-2 days), are expensive (~£42 to the consumer) and require highly skilled personnel. Antigen tests (such as Covid-19 lateral flow tests) offer rapid (15-30 minutes) and portable analysis; however, they have a much lower level of sensitivity that may not be sufficient for some applications. The aim of this project is to develop a device that is sufficiently rapid and accurate enough for health professionals to diagnose viral diseases and give patients the most appropriate treatment and/or isolate them as quickly as possible if appropriate. In this proposal, fluorescent probes composed of semiconductor quantum dot (QD) nanocrystals with molecularly imprinted polymers (MIP) will be developed to detect viral samples in saliva. We aim to achieve this goal by exploiting the QDs' unique properties: monodispersity in solution, high surface area-to-volume ratio, stable fluorescence for binding measurements, high fluorescence quantum yield (90-100%), and size and shape-dependent properties. We will synthesize non-toxic QDs that are free from cadmium, and modify their surface to make them water-soluble, compact and stable. We will link them to MIPs that bind specifically to the viral particles. MIPs are often referred to as "plastic" antibodies and can bind strongly and stably to their targets. Once the viral particles come into contact with the QDs-MIPs, they will bind to the MIP, which will result in the QDs translating the binding interaction by generating a unique fluorescence signal for the detected virus. These QDs will be ideal for platforms such as paper strips and lateral flow devices. Our aim is to use them in a prototype microfluidic paper analytic device. This will involve creating microfluidic channels on the paper device and binding the QDs-MIP probes onto the paper surface to allow the virus to be detected fluorescently via the naked eye. The versatility and agility of the proposed concept will ensure that the sensor can be modified quickly to address any potential future mutations or new outbreaks caused by other infectious pathogens.