Nucleic-Acid-Templated Synthesis of Smart Polymer Vectors for Gene Delivery

Nucleic acids are information-rich and readily available biomolecules, which can be used to template the polymerization of synthetic macromolecules. Here, we highlight the control over the size, composition, and sequence one can nowadays obtain by using this methodology. We also highlight how templated processes exploiting dynamic covalent polymerization can, in return, result in therapeutic nucleic acids fabricating their own dynamic delivery vector - a biomimicking concept that can provide original solutions for gene therapies.

From Interaction to Function in DNA-Templated Supramolecular Self-Assemblies

DNA-templated self-assembly represents a rich and growing subset of supramolecular chemistry where functional self-assemblies are programmed in a versatile manner using nucleic acids as readily-available and readily-tunable templates. In this review, we summarize the different DNA recognition modes and the basic supramolecular interactions at play in this context. We discuss the recent results that report the DNA-templated self-assembly of small molecules into complex yet precise nanoarrays, going from 1D to 3D architectures. Finally, we show their emerging functions as photonic/electronic nanowires, sensors, gene delivery vectors, and supramolecular catalysts, and their growing applications in a wide range of area from materials to biological sciences.

Ligand Mediated Metal Cations Exchanges within Metallo-Dynameric Solid Films

Dynameric solid films may be generated via the adequate imine-bond connection between bis(pyridine-2,6-diimine) core centres, coordinated with different metal cations and diaminoPEG connectors. The adequate selection of metal cations leads to cross-linked metallo-dynameric films, allowing the fine modulation of their colour and mechanical property. The coordination of the metal cations and bis(pyridine-2,6-diimine), results in the formation of interlocked structures, leading to the most probably formation of interweaved structures with better mechanical properties than those formed in the absence of the metallic cations. Removal and addition of metal cations from solid films can be achieved via tris(2-aminoethyl)amine (TREN) complexing agent, which strongly binds the metal cations, followed by subsequent insertion of other metallic cations. It allows a ligand-modulated dynamic release of the metal cations from the solid films, together with colour transfer and change of mechanical strength at the interfaces between various solid films.

Control of helical chirality in supramolecular chromophore-DNA architectures

Four different d- and l-configured chromophore-2'-deoxyuridine conjugates were applied to elucidate the helical chirality of their non-covalent assemblies along the d- and l-configured DNA templates by optical spectroscopy. There is no configuration-selective recognition between these nucleosides and the DNA templates. The helicity of the DNA assemblies is either controlled by the configuration of the DNA template or by the nucleoside configuration.

Plasmonic Heterodimers with Binding Site-Dependent Hot Spot for Surface-Enhanced Raman Scattering

A novel plasmonic heterodimer nanostructure with a controllable self-assembled hot spot is fabricated by the conjugation of individual Au@Ag core-shell nanocubes (Au@Ag NCs) and varisized gold nanospheres (GNSs) via the biotin-streptavidin interaction from the ensemble to the single-assembly level. Due to their featured configurations, three types of heterogeneous nanostructures referred to as Vertice, Vicinity, and Middle are proposed and a single hot spot forms between the nanocube and nanosphere, which exhibits distinct diversity in surface plasmon resonance effect. Herein, the calculated surface-enhanced Raman scattering enhancement factors of the three types of heterodimers show a narrow distribution and can be tuned in orders of magnitude by controlling the size of GNSs onto individual Au@Ag NCs. Particularly, the Vertice heterodimer with unique configuration can provide extraordinary enhancement of the electric field for the single hot spot region due to the collaborative interaction of lightning rod effect and interparticle plasmon coupling effect. This established relationship between the architecture and the corresponding optical properties of the heterodimers provides the basis for creating controllable platforms which can be exploited in the applications of plasmonic devices, electronics, and biodetection.

Multivalent Dendrimers and their Differential Recognition of Short Single-Stranded DNAs of Various Length and Sequence

Polycationic dendrimers were generated through simple and versatile reversible amine/aldehyde-imine chemistry. The inherent CD spectroscopic signal arising from the helical structures of single-stranded DNA (ssDNA) undergoes a dramatic amplification in the presence of the synthesised polycationic dendrimers. Compared to the first-generation core molecule, the second-generation dendrimer shows high spectroscopic responses upon chiral recognition of short ssDNA, owing to the combination of self-assembly and multivalency effects. The maximum signal variation is reached at the molar ratio at which the ratio between the negative charges in ssDNA balance the positive charges of the dendrimers, thus the approach enables differential recognition of ssDNAs of different lengths. Altogether, these results accelerate the simple and systematic discovery of efficient adaptive molecules for biomimetic recognition of ssDNA with high accuracy.

From nucleobase to DNA templates for precision supramolecular assemblies and synthetic polymers

In this minireview, we report on the recent advances of utilization of nucleobases and DNA as templates to achieve well-defined supramolecular polymers, synthetic polymers, and sequence-controlled polymers.

Chiral supramolecular organization and cooperativity in DNA-templated assemblies of ZnII–chromophore complexes

Templated cooperative binding induced assembly of chromophores is achieved via interactions between Zn-complexes and the DNA phosphodiester backbone.