a Efficiency of blocking peptides is evaluated by measuring the binding probability of the interaction between the S1 subunit and ACE2 receptor on model surface before and after incubation of the functionalized AFM tip with the four different peptides at increasing concentration (1–100 µM). b Histograms, with the corresponding data points overlaid in dark gray, showing the binding probability without peptide (0 µM) and upon incubation with 1, 10, or 100 µM of ACE2-derived peptides ([22–44], [22–57], [22–44–g–351–357], and [351–357]). The binding probability measured with a polyethylene glycol (PEG) tip enables to evaluate the nonspecific binding level. The prediction of the structure of the ACE2-derived peptides is shown in the inset. The structure of the peptides is based on the structure of the peptide in the crystal structure (PDB ID: 6m0j). For the [22–44–g–351–357] peptide, its structure was generated using homology modeling41. The error bar indicates s.d. of the mean value. c Graph showing the reduction of the binding probability. Control with ddH2O is provided in the inset showing that repetitive measurements do not result in a similar decrease of the binding probability. Data are representative of at least N = 3 independent experiments (tips and sample) per peptide concentration. P value was determined by two-sample t test in Origin. The error bar indicates s.d. of the mean value. Source data are provided as a Source Data file.