Kinetically controlled self-assembly of redox-active ferrocene–diphenylalanine: from nanospheres to nanofibers

Putting metals into organic compounds such as peptides can lead to many new desirable properties. Here we designed a novel bioorganometallic molecule, ferrocene–diphenylalanine (Fc–FF), and investigated its self-assembly behavior. We directly observed a morphological transition from metastable nanospheres to nanofibers, which led to the formation of a self-supporting hydrogel. The strong hydrophobic interaction of the Fc moiety was suggested to have a key role in this kinetically controlled self-assembly process. Moreover, the redox center of the ferrocene group further allowed us to reversibly control the self-assembly behavior of Fc–FF by altering its redox state.