Orderly self-assembly promoting the photodynamic properties of BODIPY-based hydrogen-bonded organic frameworks

A BODIPY-based H 4 BP-HOF is constructed from non-orthogonal dimers. • Differing from monomers and random aggregates, its ordered structure enhances the ROS generation efficiency. • This H 4 BP-HOF displays excellent photodynamic antibacterial activity, advancing novel photosensitizer design. Hydrogen-bonded organic frameworks (HOFs), which are assembled by organic building blocks mainly via hydrogen bonds in a controlled manner, provide an ideal platform for modulating the optical properties of conjugated fluorophores. Herein, a non-orthogonal boron dipyrromethene (BODIPY) dimer-based fluorophore carrying four carboxylic acid groups (H 4 BP) was synthesized and used to construct HOF nanosheets via H-bonding and π-π stacking effects. The orderly self-assembly structure in H 4 BP-HOF considerably improved the light-triggered reactive oxygen species (ROS) generation efficiency, which was much higher than that of H 4 BP monomers and randomly aggregated particles (H 4 BP-P). Under white light irradiation, H 4 BP-HOF efficiently generated singlet oxygen ( 1 O 2 ) and hydroxyl radical (•OH), and displayed a promising photodynamic antibacterial activity toward Escherichia coli . This work provides a novel BODIPY-based HOF material and a promising strategy to fabricate heavy-atom-free photosensitizers for ROS-related applications like photocatalysis and photodynamic therapy. Download: Download high-res image (235KB) Download: Download full-size image