Quantitative and Fast Detection of Neutralizing Antibodies Induced by Covid-19 Virus and Vaccine Via Efficiency Optimization of Antigen on Si Nanosheets

A quantitative and fast detection of neutralizing antibodies after vaccination or virus infection has been developing using an Efficiency Optimization of Protein (EOP) technique on specific design of Si nanosheet field-effected transistor. Under EOP (E=5×10 5 V/m and q= 0 o ), S1 antigen (an active subunit in S protein of virus) was reoriented to the best binding position during its immobilization on chip. Consequently, the antibody, anti-RBD, can efficiently bind to S1 on nanosheets. To increase sensitivity, an ultra-thin high dielectric HfO 2 was coated before a self-assembled monolayer substrate, TESUA and its attachment, S1, were added. Results showed that the detection signals were well enhanced. A standard curve of anti-RBD was obtained and can be used for quantitatively determining antibodies from unknown testing samples.