Metallo-drugs have been highly significant in the development of novel anticancer agents. Supramolecular drug agents allow the design and synthesis of a range of molecular architectures. The work in this thesis has built upon previous knowledge on this subject by undertaking novel biological studies on known metal supramolecular helicates as well as the design of a new helicate in order to improve upon existing drugs. In chapter three, the DNA three-way junction binding of a number of supramolecular cylinders is described. Three-way junction binding is a new mode of DNA recognition and relevant to the DNA replication fork, present in dividing cells. Chapter four outlines a number of novel in vitro studies on an iron supramolecular cylinder which indicate new, unsuspected and unprecedented biological actions. In chapter five biological studies of unsaturated ruthenium(II) helicates are discussed. These complexes combine a cisplatin like coordinative binding mode with a helical supramolecular design. Chapter six discusses the design of a synthetic route from an unsaturated ruthenium(II) complex to create a novel supramolecular compound with a tuneable ligand surface.