Immunoassays have become essential tools for detecting infectious viruses. However, traditional monoclonal antibody-dependent immunoassays are costly, fragile, and unstable, especially in complex media. To overcome these challenges, we have developed cost-effective, robust, and high-affinity nanobodies as alternatives to monoclonal antibodies for rapid detection applications. We engineered dual-epitope nanobody (NB) pairs and incorporated them into a sandwich immunosensor design to detect transmitted rotaviruses in rectal swabs and wastewater samples. To further enhance sensitivity, we synthesized an advanced two-dimensional material, MXenes@CNTs@AuNPs, which offers an extensive specific surface area that supports the enrichment and immobilization of NBs. This integration with catalase-modified magnetic probes facilitates signal generation. Subsequently, our sensor achieved a detection limit of 0.0207 pg/mL for the rotavirus VP6 antigen, significantly outperforming commercial antigen kits with a sensitivity enhancement of 3.77 × 10⁵-fold. The exceptional sensor performance extended to specificity, repeatability, stability, and accuracy across various sample types, establishing it as a promising tool for rotavirus detection. This research outlines a viable strategy for creating a robust and ultrasensitive analytical nanoprobe, thereby addressing the critical need for efficient and reliable viral detection methods in various environments.

中文翻译：

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基于双表位纳米抗体的免疫传感器的开发，用于轮状病毒的超灵敏检测MXenes@CNTs@AuNPs


免疫测定已成为检测传染性病毒的重要工具。然而，传统的单克隆抗体依赖性免疫测定成本高、脆弱且不稳定，尤其是在复杂培养基中。为了克服这些挑战，我们开发了经济高效、稳健且高亲和力的纳米抗体，作为用于快速检测应用的单克隆抗体的替代品。我们设计了双表位纳米抗体 （NB） 对，并将其整合到夹心免疫传感器设计中，以检测直肠拭子和废水样本中传播的轮状病毒。为了进一步提高灵敏度，我们合成了一种先进的二维材料 MXenes@CNTs@AuNPs，它提供广泛的比表面积，支持 NB 的富集和固定。这种与过氧化氢酶修饰的磁性探针的整合有助于信号的产生。随后，我们的传感器对轮状病毒 VP6 抗原的检测限达到 0.0207 pg/mL，显著优于市售抗原试剂盒，灵敏度提高了 3.77 × 10⁵ 倍。卓越的传感器性能扩展到各种样品类型的特异性、可重复性、稳定性和准确性，使其成为一种很有前途的轮状病毒检测工具。本研究概述了一种创建稳健且超灵敏的分析纳米探针的可行策略，从而满足了各种环境中对高效可靠的病毒检测方法的迫切需求。