Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States.
Antimicrobial Resistance Interdisciplinary Research Group, Singapore-MIT Alliance for Research and Technology, 1 CREATE Way, Singapore 138602.
ACS Sens. 2021 May 28;6(5):1891-1898. doi: 10.1021/acssensors.1c00235. Epub 2021 Apr 6.
Rapid and inexpensive serological tests for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies are essential to conduct large-scale seroprevalence surveys and can potentially complement nucleic acid or antigen tests at the point of care. During the COVID-19 pandemic, extreme demand for traditional lateral flow tests has stressed manufacturing capacity and supply chains. Motivated by this limitation, we developed a SARS-CoV-2 antibody test using cellulose, an alternative membrane material, and a double-antigen sandwich format. Functionalized SARS-CoV-2 antigens were used as both capture and reporter binders, replacing the anti-human antibodies currently used in lateral flow tests. The test could provide enhanced sensitivity because it labels only antibodies against SARS-CoV-2 and the signal intensity is not diminished due to other human antibodies in serum. Three-dimensional channels in the assay were designed to have consistent flow rates and be easily manufactured by folding wax-printed paper. We demonstrated that this simple, vertical flow, cellulose-based assay could detect SARS-CoV-2 antibodies in clinical samples within 15 min, and the results were consistent with those from a laboratory, bead-based chemiluminescence immunoassay that was granted emergency use approval by the US FDA.
快速且廉价的严重急性呼吸综合征冠状病毒 2（SARS-CoV-2）抗体血清学检测对于进行大规模血清流行率调查至关重要，并且可以在护理点潜在地补充核酸或抗原检测。在 COVID-19 大流行期间，对传统侧向流动检测的极端需求给制造能力和供应链带来了压力。受此限制，我们使用纤维素（一种替代膜材料）和双抗原夹心格式开发了一种 SARS-CoV-2 抗体检测。功能化的 SARS-CoV-2 抗原既可用作捕获物，也可用作报告物结合物，取代了当前侧向流动检测中使用的抗人抗体。由于该检测仅标记针对 SARS-CoV-2 的抗体，并且由于血清中的其他人类抗体而不会降低信号强度，因此它可以提供增强的灵敏度。该检测中的三维通道被设计为具有恒定的流速，并且可以通过折叠蜡印纸轻松制造。我们证明，这种简单的垂直流动基于纤维素的检测可以在 15 分钟内检测临床样本中的 SARS-CoV-2 抗体，并且结果与获得美国 FDA 紧急使用授权的实验室基于珠子的化学发光免疫分析的结果一致。
