Thanunchai Maytawan, Sangboonruang Sirikwan, Semakul Natthawat, Kumthip Kattareeya, Maneekarn Niwat, Tragoolpua Khajornsak
Division of Clinical Microbiology, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.
Infectious Diseases Research Unit (IDRU), Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai 50200, Thailand.
Biosensors (Basel). 2025 Jun 16;15(6):387. doi: 10.3390/bios15060387.
Norovirus (NoV), a leading cause of acute gastroenteritis worldwide, imposes significant morbidity and economic burdens across all age groups. Timely and accurate laboratory diagnosis is crucial for effective outbreak control and patient management. However, current diagnostic methods often require specialized equipment, technical expertise, and considerable time. To address these challenges, we developed a visual detection method utilizing gold nanoparticles (AuNPs) functionalized with the SMV25 aptamer specific to the NoV capsid protein. Detection relies on MgCl-induced changes in the color and absorbance of these aptamer-functionalized AuNPs. The assay exhibited a good linear relationship between the A630/A520 absorbance ratio and NoV capsid protein concentration. Specifically, in a buffer system, this linearity (R = 0.9026) was observed over a 0-32 ng/µL range with a limit of detection (LOD) of 9.65 ng/µL. Similarly, for NoV spiked into stool suspensions, a strong linear correlation (R = 0.9170) was found across a 0-100 ng/µL range, with an LOD of 37.11 ng/µL. Evaluation with real stool samples yielded 77% sensitivity and 65% specificity. Notably, the assay demonstrated the highest sensitivity towards NoV GII.2 (100%), followed by GII.4 (78%). Scanning transmission electron microscopy confirmed the underlying aggregation and dispersion patterns of the aptamer-functionalized AuNPs. This colorimetric assay provides a simple, rapid, and visual method for NoV detection. Nevertheless, further enhancements are necessary to improve its performance in the direct testing of complex specimens, paving the way for future on-site detection applications, especially in resource-limited settings.
诺如病毒（NoV）是全球急性胃肠炎的主要病因，给所有年龄组带来了重大的发病负担和经济负担。及时准确的实验室诊断对于有效控制疫情和管理患者至关重要。然而，目前的诊断方法通常需要专门的设备、技术专长和相当长的时间。为应对这些挑战，我们开发了一种视觉检测方法，该方法利用用诺如病毒衣壳蛋白特异性的SMV25适配体功能化的金纳米颗粒（AuNPs）。检测依赖于MgCl诱导的这些适配体功能化AuNPs的颜色和吸光度变化。该检测方法在A630/A520吸光度比值与诺如病毒衣壳蛋白浓度之间表现出良好的线性关系。具体而言，在缓冲液系统中，在0至32 ng/µL范围内观察到这种线性关系（R = 0.9026），检测限（LOD）为9.65 ng/µL。同样，对于添加到粪便悬液中的诺如病毒，在0至100 ng/µL范围内发现了很强的线性相关性（R = 0.9170），检测限为37.11 ng/µL。用实际粪便样本进行评估，灵敏度为77%，特异性为65%。值得注意的是，该检测方法对诺如病毒GII.2的灵敏度最高（100%），其次是GII.4（78%）。扫描透射电子显微镜证实了适配体功能化AuNPs的潜在聚集和分散模式。这种比色法为诺如病毒检测提供了一种简单、快速且可视化的方法。然而，需要进一步改进以提高其在直接检测复杂样本中的性能，为未来的现场检测应用铺平道路，特别是在资源有限的环境中。
