Figure 1.

Conventional SELEX for generating DNA aptamers [8]. A random DNA library, typically containing 10¹⁴–10¹⁶ unique sequences of single-stranded oligonucleotides, is incubated with the target molecule of interest. The target-bound and unbound sequences are separated, and the target-bound sequences are amplified by PCR for use as inputs in the next round of selection. The reiterated rounds of selection are carried out to generate a pool of aptamer sequences that have high affinity for the target molecule. These aptamers are then cloned and sequenced.