Adi Wihan, Biswas Dhruv, Shelef Miriam A, Yesilkoy Filiz
Department of Biomedical Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA.
Department of Medicine, University of Wisconsin-Madison, Madison, WI 53705, USA.
Biomed Opt Express. 2022 Mar 16;13(4):2130-2143. doi: 10.1364/BOE.454919. eCollection 2022 Apr 1.
Serological assays that can reveal immune status against COVID-19 play a critical role in informing individual and public healthcare decisions. Currently, antibody tests are performed in central clinical laboratories, limiting broad access to diverse populations. Here we report a multiplexed and label-free nanoplasmonic biosensor that can be deployed for point-of-care antibody profiling. Our optical imaging-based approach can simultaneously quantify antigen-specific antibody response against SARS-CoV-2 spike and nucleocapsid proteins from 50 µL of human sera. To enhance the dynamic range, we employed multivariate data processing and multi-color imaging and achieved a quantification range of 0.1-100 µg/mL. We measured sera from a COVID-19 acute and convalescent (N = 24) patient cohort and negative controls (N = 5) and showed highly sensitive and specific past-infection diagnosis. Our results were benchmarked against an electrochemiluminescence assay and showed good concordance (R∼0.87). Our integrated nanoplasmonic biosensor has the potential to be used in epidemiological sero-profiling and vaccine studies.
能够揭示针对新冠病毒免疫状态的血清学检测在为个人和公共医疗决策提供信息方面发挥着关键作用。目前，抗体检测在中央临床实验室进行，限制了不同人群的广泛使用。在此，我们报告了一种可用于即时护理抗体分析的多重且无标记的纳米等离子体生物传感器。我们基于光学成像的方法能够同时从50微升人血清中定量针对新冠病毒刺突蛋白和核衣壳蛋白的抗原特异性抗体反应。为了扩大动态范围，我们采用了多变量数据处理和多色成像，实现了0.1 - 100微克/毫升的定量范围。我们检测了一组新冠病毒急性期和康复期患者（N = 24）以及阴性对照（N = 5）的血清，显示出对既往感染诊断具有高灵敏度和特异性。我们的结果与电化学发光检测进行了对比，显示出良好的一致性（R ∼ 0.87）。我们集成的纳米等离子体生物传感器有潜力用于流行病学血清分析和疫苗研究。
