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现场快速定量检测新型冠状病毒(SARS-CoV-2)抗体对于监测新型冠状病毒感染的肺炎患者治疗过程具有重要作用.目前,大多数抗体检测采用基于金纳米粒子的免疫层析定性检测,但该方法仅表现出一种颜色变化,无法实现现场快速定量检测.本文采用特异性刻蚀金纳米棒(Au NRs)的方法,实现了SARS-CoV-2抗体多色彩可视化的现场快速定量检测.首先,将SARS-CoV-2重组抗原固定在96孔酶标板上;随后,将辣根过氧化物酶标记的酶标抗体与待测抗体结合,形成抗原-待测抗体-酶标抗体的复合三明治结构,且酶标抗体与待测抗体浓度呈正相关;由于酶标抗体可与3,3′,5,5′-四甲基联苯胺(TMB)发生特异性反应,生成TMB2+,而TMB2+可选择性刻蚀Au NRs,使得溶液产生丰富多彩的颜色,即可通过观察溶液颜色变化实现SARS-CoV-2抗体浓度半定量检测.在最佳条件下,该方法对SARS-CoV-2 IgM抗体在5.00～200 IU浓度范围内呈良好线性关系,检出限为1.29 IU,并具有较高的灵敏度和特异性.上述方法成功用于COVID-19患者治疗过程中SARS-CoV-2 IgM抗体浓度半定量快速检测.“,”Rapid detection of body fluid severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) antibody is an effective strategy for infection therapeutic effect of coronavirus disease(COVID-19). Most detec?tion methods require relatively large equipment,which limited their on-site application. Lateral flow immuno?assay(LFIA) can be used to qualitative antibody detection based on the aggregation of gold nanoparticles (Au NPs),which exhibits just one-color change and cannot realize rapid quantitative detection without the help of additional equipment. In this study,a high-resolution multicolor colorimetric strategy was developed and applied to assessing antibody concentration at a glance based on etching of gold nanorods(Au NRs). Firstly,SARS-CoV-2 recombinant antigen was immobilized on the surface of the 96-wells. Then,horseradish peroxidase(HRP)-labeled second antibody combined with antibody to form an antigen-antibody-secondary antibody complex on the well surface,which has direct relationship with antibody concentration in the sample and can be used to oxidize 3,3′,5,5′-tetramethylbenzidine(TMB)to form TMB2+at the presence of HRP. The generation of TMB2+ efficiently etch Au NRs to produce multicolor solution. The etching result in vivid color changes in the system has a relationship with the amount of SARS-CoV-2 IgM antibody. Under the optimal conditions,the proposed strategy exhibited a linear response in the 5.00―200 IU concentration range,and a detection limit of 1.29 IU for SARS-CoV-2 IgM antibody,with high sensitivity and specificity. This assay is prospective for the on-site semi-quantitative visual detection of SARS-CoV-2 IgM antibody concentration in the COVID-19 therapeutic process.