蛋白質檢測，ELISA assay我也做的很多

rt-pcr, ELISA assay 都是最常見的生物學測試。covid test測的是核酸，不是蛋白，和spike 大小沒有關係。

在多說一句吧，現在測covid19核酸檢測測的一種核鞘蛋白virus nucleocapsid (N)。既不測spike 蛋白也不測S protein的 mRNA

The oligonucleotide primers and probes for detection of 2019-nCoV were selected from regions of the virus nucleocapsid (N) gene. The panel is designed for specific detection of SARS-CoV-2 (two primer/probe sets). An additional primer/probe set to detect the human RNase P gene (RP) in control samples and clinical specimens is also included in the panel.