Analysis of Metallo-Supramolecular Systems utilizing Single-Molecule Force Spectroscopy

Kudera, Michael; Eschbaumer, Christian; Gaub, Hermann E.; Schubert, Ulrich S.
Abstract:
Single-molecule force spectroscopy has been used for the investigation of the rupture behavior of individual metallo-supramolecular systems. For this purpose, a specifically designed unsymmetrical ,-functionalized poly(ethylene oxide) has been employed for mono-termination with a terpyridine ligand and subsequently for the attachment onto atomic force microscopy (AFM) tips and microscope slide substrates. Metallo-supramolecular complexes were formed by the use of ruthenium(III)-ruthenium(II) chemistry. Vertical stretching with the AFM cantilever ruptured the coordinative bonds. The rupture force of individual bisterpyridine ruthenium(II) complexes was determined to be 95 pN at a force loading rate of 1 nN s-1. Simultaneous rupturing of multiple parallel metallo-supramolecular bonds was also observed. Monte Carlo simulations corroborated the experimental observations. The presented results lay the basis for the application of such metallo-supramolecular systems in advanced functional nanomaterials.
Year:
2003
Type of Publication:
Article
Journal:
Advanced Functional Materials
Volume:
13
Pages:
615 – 620