The outbreak of COVID-19 and its continued spread have seriously threatened public health. Antibody testing is essential for infection diagnosis, seroepidemiological analysis, and vaccine evaluation. However, convenient, fast, and accurate antibody detection remains a challenge in this protracted battle. Here, we report an ultrafast, low-cost, label-free, and portable SARS-CoV-2 immunoglobulin G (IgG) detection platform based on organic electrochemical transistors (OECTs), which can be remotely controlled by a mobile phone. To enable faster detection, voltage pulses are applied on the gate electrode of the OECT to accelerate binding between the antibody and antigen. By optimizing ion concentrations and pH values of test solutions, we realize specific detection of SARS-CoV-2 IgG in several minutes with a detectable region from 10 fM to 100 nM, which encompasses the range of serum SARS-CoV-2 IgG levels in humans. These portable sensors show promise for use in diagnosis and prognosis of COVID-19.

中文翻译：

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使用灵活的有机电化学晶体管对 COVID-19 IgG 进行超快速、灵敏和便携的检测

COVID-19 的爆发及其持续传播已严重威胁公共健康。抗体检测对于感染诊断、血清流行病学分析和疫苗评估至关重要。然而，在这场旷日持久的战斗中，方便、快速、准确的抗体检测仍然是一个挑战。在这里，我们报告了一种基于有机电化学晶体管 (OECT) 的超快速、低成本、无标记和便携式 SARS-CoV-2 免疫球蛋白 G (IgG) 检测平台，该平台可以通过手机进行远程控制。为了实现更快的检测，在 OECT 的栅电极上施加电压脉冲以加速抗体和抗原之间的结合。通过优化测试溶液的离子浓度和pH值，我们实现了在几分钟内特异性检测SARS-CoV-2 IgG，可检测区域从10 fM到100 nM，其中包括人类血清 SARS-CoV-2 IgG 水平的范围。这些便携式传感器有望用于 COVID-19 的诊断和预后。