Defining a stem length-dependent binding mechanism for the cocaine-binding aptamer. A combined NMR and calorimetry study

A combined approach of NMR spectroscopy and isothermal titration calorimetry (ITC) is used for determining the ligand-binding mechanism used by a cocaine-binding aptamer. Chemical shift perturbation data and the observation of intermolecular NOEs have shown that the three-way junction is the site of ligand binding.