School of Chemistry and Physics, Faculty of Science, Queensland University of Technology (QUT), 2 George Street, Brisbane, QLD 4000, Australia.
Griffith Institute for Drug Discovery (GRIDD), Griffith University, QLD, Australia; Menzies Health Institute Queensland (MIHQ), Griffith University, QLD, Australia.
SLAS Discov. 2022 Sep;27(6):331-336. doi: 10.1016/j.slasd.2022.06.001. Epub 2022 Jun 4.
Current methods for the screening of viral infections in clinical settings, such as reverse transcription polymerase chain reaction (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA), are expensive, time-consuming, require trained personnel and sophisticated instruments. Therefore, novel sensors that can save time and cost are required specially in remote areas and developing countries that may lack the advanced scientific infrastructure for this task. In this work, we present a sensitive, and highly specific biosensing approach for the detection of harmful viruses that have cysteine residues within the structure of their cell surface proteins. We utilized new method for the rapid screening of SARS-CoV-2 virus in biological fluids through its S1 protein by surface enhanced Raman spectroscopy (SERS). The protein is captured from aqueous solutions and biological specimens using a target-specific extractor substrate. The structure of the purified protein is then modified to convert it into a bio-thiol by breaking the disulfide bonds and freeing up the sulfhydryl (SH) groups of the cysteine residues. The formed biothiol chemisorbs favourably onto a highly sensitive plasmonic sensor and probed by a handheld Raman device in few seconds. The new method was used to screen the S1 protein in aqueous medium, spiked human blood plasma, mucus, and saliva samples down to 150 fg/L. The label-free SERS biosensing method has strong potential for the fingerprint identification many viruses (e.g. the human immunodeficiency virus, the human polyomavirus, the human papilloma virus, the adeno associated viruses, the enteroviruses) through the cysteine residues of their capsid proteins. The new method can be applied at points of care (POC) in remote areas and developing countries lacking sophisticated scientific infrastructure.
目前临床环境中病毒感染的筛查方法，如逆转录聚合酶链反应（RT-qPCR）和酶联免疫吸附测定（ELISA），既昂贵又耗时，需要经过培训的人员和复杂的仪器。因此，特别是在缺乏先进科学基础设施的偏远地区和发展中国家，需要有能够节省时间和成本的新型传感器。在这项工作中，我们提出了一种用于检测细胞表面蛋白结构中含有半胱氨酸残基的有害病毒的灵敏、高度特异的生物传感方法。我们利用表面增强拉曼光谱（SERS）技术，通过其 S1 蛋白快速筛选 SARS-CoV-2 病毒的新方法，对生物体液中的 SARS-CoV-2 病毒进行检测。该方法利用目标特异性提取剂底物从水溶液和生物标本中捕获蛋白质。然后，通过打破二硫键并释放半胱氨酸残基的巯基（SH）基团，将纯化的蛋白质结构修饰为生物硫醇。形成的生物硫醇通过高度灵敏的等离子体传感器有利地化学吸附，并在几秒钟内通过手持式拉曼设备进行探测。该新方法用于在水介质、加标人血浆、黏液和唾液样本中筛选 S1 蛋白，检测下限低至 150 fg/L。该无标记 SERS 生物传感方法具有通过其衣壳蛋白中的半胱氨酸残基对许多病毒（如人类免疫缺陷病毒、人类多瘤病毒、人类乳头瘤病毒、腺相关病毒、肠道病毒）进行指纹识别的强大潜力。该新方法可应用于缺乏复杂科学基础设施的偏远地区和发展中国家的即时护理点（POC）。
