Isolation and characterization of enantioselective DNA aptamers for ibuprofen

Single stranded DNA aptamers that can bind to ibuprofen, a widely used anti-inflammation drug, were selected from random DNA library of 10¹⁵ nucleotides by FluMag-SELEX process. Five different sequences were selected and their enantioselectivity and affinity were characterized. Three out of five aptamer candidates did not show any affinity to (S)-ibuprofen, but only to racemic form of ibuprofen, suggesting that they are (R)-ibuprofen specific aptamers. Another two aptamer candidates showed affinity to both racemic form and (S)-ibuprofen, which were considered as (S)-ibuprofen specific aptamers. The affinity of five ssDNA aptamers isolated was in a range of 1.5-5.2 μM. In addition, all of these five aptamers did not show any affinity to analogues of ibuprofen in its profen's group (fenoprofen, flubiprofen, and naproxen) and the antibiotics of oxytetracycline, another control.