Using spectroscopic techniques to examine drug–DNA interactions

Since the first x-ray structures of DNA revealed that the structure was sensitive to the environment from which it was crystallized, a combination of biophysical methods has been developed to probe structural changes that occur when molecules and metal complexes interact with DNA. Metal complexes that exhibit noncoordinate interactions such as intercalation and groove binding have been used to probe the structural complexity of DNA, whereas covalent binders like cisplatin are anticancer agents. Advances in spectroscopic techniques allow DNA interactions to be examined in far greater detail, yielding important structural information on binding. With this information, innovative drugs can be designed and synthesized to incorporate more than one binding characteristic to improve their therapeutic effect. In this chapter, we report on the use of spectroscopic methods to elucidate the interactions of small molecules with DNA.