BODIPY-based self-assembled Structures
BODIPY dyes have attracted considerable attention in the past decades due to their excellent optical, photophysical and electronic properties, high chemical and physiological stability as well as ease in chemical functionalization. Their planar geometry anticipates facile stacking of the dipyrromethene core through aromatic interactions, which has been exploited to construct various supramolecular structures in solution and the solid state. Our group currently focuses on the design of hydrophobic and amphiphilic BODIPY dye molecules and understanding the fundamentals of their self-assembly processes in solution and the solid state. For instance, various BODIPY dye aggregates with alternated chromophore arrangement as well as H- and J-type excitonic coupling have been thoroughly investigated in our group. Controlling the molecular arrangement is key to understanding the functionalities of this class of fluorescent dyes, yielding promising functional materials for optoelectronic or biomedical applications.
A. Rödle et. al. Polymer 2017, http://dx.doi.org/10.1016/j.polymer.2016.12.050.
A. Rödle et. al. Chem. Eur. J. 2016, 22, 15772.
N. K. Allampally et. al., Chem. Eur. J. 2014, 20, 10669.
Metallosupramolecular Polymers based on discrete p-conjugated molecules
Supramolecular polymers are materials with polymeric properties whose monomer units are held together by reversible non-covalent interactions. One of the most successful strategies to create highly ordered supramolecular polymers consists in introducing aromatic interactions and/or hydrogen bonds. However, the exploitation of other –less conventional- weak forces has been explored to a much lesser extent. In our group, the self-assembly of discrete Pd(II), Zn(II) and Pt(II) metal complexes based on p-conjugated ligands is investigated through a variety of techniques in solution and in the slid state. Due to the presence of multiple polarized atoms, i.e. halogen ligands, metal ions or polarized CH groups, these systems are able to self-assemble into ordered supramolecular polymers driven by multiple weak interactions, such as metal-metal and weak CH hydrogen bonding. The presence of an extended p-surface as well as metal ions make these system potential candidates for optoelectronic applications.
L. Herkert et. al. CrystEngComm. 2016, 18, 8813.
N. K. Allampally et. al. Chem. Eur. J. 2016, 22, 7810.
C. Rest et. al. Angew. Chem. Int. Ed. 2014, 53, 700; Chem. Commun. 2014, 50, 13366.
M. J. Mayoral et. al. J. Am. Chem. Soc. 2013, 135, 2148.
Self-Assembled Structures for Biomedical Applications
Some of the previously described amphiphilic self-assembled structures have a great potential to be applied in biomedicine, for instance as drug delivery vehicles in cancer therapy. For instance, our group currently tests the ability of various nanoparticle assemblies to encapsulate and transport anticancer drugs by exploiting the enhanced permeability and retention (EPR) effect, by which aggregates of a certain size (usually between 10-200 nm) are prone of accumulation in tumor tissues.