A rapid test for detecting total immunoglobulins directed towards the nucleocapsid protein (N) of severe acute syndrome coronavirus 2 (SARS CoV-2) was developed, based on a multi-target lateral flow immunoassay comprising two test lines. Both test lines bound to several classes of immunoglobulins (G, M, and A). Specific anti-SARS immunoglobulins were revealed by a colorimetric probe formed by N and gold nanoparticles. Targeting the total antibodies response to infection enabled achieving 100% diagnostic specificity (95.75–100, C.I. 95%, n = 85 healthy and with other infections individuals) and 94.6% sensitivity (84.9–98.9, C.I. 95%, n = 62 SARS CoV-2 infected subjects) as early as 7 days post confirmation of positivity. Agreeing results with a reference serological ELISA were achieved, except for the earlier detection capability of the rapid test. Follow up of the three seroconverting patients endorsed the hypothesis of the random rise of the different immunoglobulins and strengthened the ‘total antibodies’ approach for the trustworthy detection of serological response to SARS CoV-2 infection.

基于包含两条测试线的多目标横向流免疫分析，开发了一种快速检测针对严重急性综合症冠状病毒2（SARS CoV-2）核衣壳蛋白（N）的总免疫球蛋白的方法。两条测试线都结合了几类免疫球蛋白（G，M和A）。N和金纳米颗粒形成的比色探针揭示了特异性抗SARS免疫球蛋白。以针对感染的总抗体反应为目标，可以实现100％的诊断特异性（95.75–100，CI 95％，n = 85健康和其他感染个体）和94.6％的敏感性（84.9–98.9，CI 95％，n = 62 SARS CoV -2受感染的受试者）最早在确认阳性后的7天之内。除了快速检测的早期检测能力外，还获得了与参考血清学ELISA一致的结果。