Flow cytometry histogram showing binding competition between the labeled and unlabeled SL₂-B aptamer in HT-29 cells and quantitative analysis of flow cytometry result.

Red – 0 nM (negative control), green – aptamer binding without excess of unlabeled SL₂-B aptamer (0.5 nM); pink – aptamer binding in excess of unlabeled SL₂-B aptamer (unlabeled aptamer – 10 nM, labeled aptamer – 0.5 nM). *Significant difference from the negative control sample at p-value<0.05; **Significant difference from the negative control sample at p-value<0.001.