Schematic of Adherent Cell-SELEX (AC-SELEX) Procedure.

A starting library of >10¹⁵ aptamers was utilized and eighteen rounds of AC-SELEX were carried out to purify and amplify the aptamers which recognized epitopes present on HF cells and not present on HeLa cells. The starting library was first incubated with the HeLa cell line and the unbound aptamers were recovered and utilized for the AC-SELEX procedure.