Analysis of ATP and AMP binding to a DNA aptamer and its imidazole-tethered derivatives by surface plasmon resonance

Imidazole was tethered to the C5 position of thymine in an ATP-binding DNA aptamer with two types of linkers, and the affinities of each aptamer for ATP and AMP were determined by surface plasmon resonance measurements. The imidazole-tethered aptamers exhibited higher affinity for ATP, almost independently of the linker structure or the modification site.