Measurements of Anti-SARS-CoV-2 Antibody Levels after Vaccination Using a SH-SAW Biosensor

Abstract

To prevent the COVID-19 pandemic that threatens human health, vaccination has become a useful and necessary tool in the response to the pandemic. The vaccine not only induces antibodies in the body, but may also cause adverse effects such as fatigue, muscle pain, blood clots, and myocarditis, especially in patients with chronic disease. To reduce unnecessary vaccinations, it is becoming increasingly important to monitor the amount of anti-SARS-CoV-2 S protein antibodies prior to vaccination. A novel SH-SAW biosensor, coated with SARS-CoV-2 spike protein, can help quantify the amount of anti-SARS-CoV-2 S protein antibodies with 5 μL of finger blood within 40 s. The LoD of the spike-protein-coated SAW biosensor was determined to be 41.91 BAU/mL, and the cut-off point was determined to be 50 BAU/mL (Youden’s J statistic = 0.94733). By using the SH-SAW biosensor, we found that the total anti-SARS-CoV-2 S protein antibody concentrations spiked 10−14 days after the first vaccination (p = 0.0002) and 7−9 days after the second vaccination (p = 0.0116). Furthermore, mRNA vaccines, such as Moderna or BNT, could achieve higher concentrations of total anti-SARS-CoV-2 S protein antibodies compared with adenovirus vaccine, AZ (p < 0.0001). SH-SAW sensors in vitro diagnostic systems are a simple and powerful technology to investigate the local prevalence of COVID-19.

Keywords: SARS-CoV-2; SH-SAW biosensor; antibody; vaccine.

Figure 1

The dual-channel SH-SAW sensor chip. (a) Photograph of SH-SAW sensor chip; (b) schematic coated proteins in the dual-channel SH-SAW sensor chip.

Figure 2

Physical photograph of the iProtin immunoassay and SH-SAW sensor chip coated with SARS-CoV-2 S protein.

Figure 3

Real-time measurement of various concentrations of total anti-S protein antibodies in the reference and capture channels.

Figure 4

Establishment of four parameter logistics (4PL) standard curve.

Figure 5

Receiver operating characteristic (ROC) analysis of S protein coated SAW biosensors.

Figure 6

Distribution of vaccine brands received by subjects.

Figure 7

Follow-up and comparison of total anti-SARS-CoV-2 S protein antibody concentrations after the first (a,c) and second (b,d) vaccination. (a,b) All brands of vaccines; (c,d) different brands of vaccines.

Figure 8

Follow-up measurements of anti-SARS-CoV-2 S protein total antibodies (a) at the indicated days after the first vaccination (b) at the indicated days after the second vaccination. Each line represents the concentration of antibodies in the blood continuously measured after receiving one brand of vaccine on the specified date.