Porphyrin complex species and solid state devices: from solution to solid state using non covalent approaches”

Understanding and control of non-covalent interactions, driving spontaneous self-assembly of molecules (in solution or at specific interfaces) and leading to designed supramolecular architectures is, nowadays, fundamental to develop selective host-guest systems to satisfy the tremendous specificity requirements of nanotechnology and biotechnology. The feasibility of synthesizing stable complexes in aqueous solution is based on the exploitation of water-soluble but solvophobic molecular components. Porphyrins and corroles, no doubts, represent one of the most versatile macrocyclic classes able to selectively interact with a wide selection of scaffolds, ranging from biological template (i.e nucleic acids, proteins, polyelectrolites), organic macromolecules (i.e. calixarenes) to inorganic nanomaterials (metal and oxides nanoparticles, graphene oxide). In fact, following a careful molecular and supramolecular design, the dichotomic nature of the components drives spontaneous self-assembly mainly leading from hydrophobic interactions. Since hybrid molecular-based nanomaterials represent, nowadays, a successful solution to satisfy technological demands of chemical memory devices and selective sensors, the successful transferring of porphyrin complex assembly from aqueous solution to solid surface appear promising for a rationale device design, achieved by modulating surface properties and host-guest chemistry (Figure 1). In fact, porphyrins represent a valid example of stimuli-responsive chromophores, possess an intrinsic chirality, have a reported efficiency as antitumoral drugs as well as a proven ability as specific reporters of nucleic acids conformations. Our final goal is, thus, the development of a sensing system able to discriminate chiral molecules through a subtle interplay between supramolecular chemistry and interfacial science leading to robust surface grafting and effective detection at surfaces.