Dual-Input Regulation and Positional Control in Hybrid Oligonucleotide/Discotic Supramolecular Wires

Assembly of Dynamic Supramolecular Polymers on a DNA Origami Platform

Biological processes rely on transient interactions that govern assembly of biomolecules into higher order, multi-component systems. A synthetic platform for the dynamic assembly of multicomponent complexes would provide novel entries to study and modulate the assembly of artificial systems into higher order topologies. Here, we establish a hybrid DNA origami-based approach as an assembly platform that enables dynamic templating of supramolecular architectures. It entails the site-selective recruitment of supramolecular polymers to the platform with preservation of the intrinsic dynamics and reversibility of the assembly process. The composition of the supramolecular assembly on the platform can be tuned dynamically, allowing for monomer rearrangement and inclusion of molecular cargo. This work should aid the study of supramolecular structures in their native environment in real-time and incites new strategies for controlled multicomponent self-assembly of synthetic building blocks.

Assembly and functionalization of supramolecular polymers from DNA-conjugated squaraine oligomers

DNA conjugated oligomers of organic molecules are candidates for applications in the materials and medical sciences, in diagnostics, in optical devices, for delivery or for the design of complex molecular architectures. Herein, we describe the synthesis and properties of DNA-conjugated squaraine (Sq) oligomers. The oligomers self-assemble into supramolecular polymers that are amenable to further functionalization via DNA hybridization, as shown by the attachment of gold nanoparticles (AuNPs).

The assembly of supramolecular polymers of DNA-linked squaraine oligomers and their subsequent derivatization is described.

Anchoring Supramolecular Polymers to Human Red Blood Cells by Combining Dynamic Covalent and Non-Covalent Chemistries

Understanding cell/material interactions is essential to design functional cell-responsive materials. While the scientific literature abounds with formulations of biomimetic materials, only a fraction of them focused on mechanisms of the molecular interactions between cells and material. To provide new knowledge on the strategies for materials/cell recognition and binding, supramolecular benzene-1,3,5-tricarboxamide copolymers bearing benzoxaborole moieties are anchored on the surface of human erythrocytes via benzoxaborole/sialic-acid binding. This interaction based on both dynamic covalent and non-covalent chemistries is visualized in real time by means of total internal reflection fluorescence microscopy. Exploiting this imaging method, we observe that the functional copolymers specifically interact with the cell surface. An optimal fiber affinity towards the cells as a function of benzoxaborole concentration demonstrates the crucial role of multivalency in these cell/material interactions.

Light-Responsive Arylazopyrazole Gelators: From Organic to Aqueous Media and from Supramolecular to Dynamic Covalent Chemistry

Versatile photoresponsive gels based on tripodal low molecular weight gelators (LMWGs) are reported. A cyclohexane-1,3,5-tricarboxamide (CTA) core provides face-to-face hydrogen bonding and a planar conformation, inducing the self-assembly of supramolecular polymers. The CTA core was substituted with three arylazopyrazole (AAP) arms. AAP is a molecular photoswitch that isomerizes reversibly under alternating UV and green light irradiation. The E isomer of AAP is planar, favoring the self-assembly, whereas the Z isomer has a twisted structure, leading to a disassembly of the supramolecular polymers. By using tailor-made molecular design of the tripodal gelator, light-responsive organogels and hydrogels were obtained. Additionally, in the case of the hydrogels, AAP was coupled to the core through hydrazones, so that the hydrogelator and, hence, the photoresponsive hydrogel could also be assembled and disassembled by using dynamic covalent chemistry.