Three-Dimensional Nucleic Acid Nanostructures Based on Self-Assembled Polymer-Oligonucleotide Conjugates of Comblike and Coil-Comb Chain Architectures

Abstract

Spherical nucleic acids have emerged as a class of nanostructures, exhibiting a wide variety of properties, distinctly different from those of linear nucleic acids, and a plethora of applications in therapeutics and diagnostics. Herein, we report on preparation of 3D nucleic acid nanostructures, prepared by self-assembly of polymer–oligonucleotide conjugates. The latter are obtained by grafting multiple alkyne-functionalized oligonucleotide strands onto azide-modified homo-, block, and random (co)­polymers of chloromethylstyrene via initiator-free click coupling chemistry to form conjugates of comblike and coil-comb chain architectures. The resulting conjugates are amphiphilic and form stable nanosized supramolecular structures in aqueous solution. The nanoconstructs are thoroughly investigated and a number of physical characteristics, in particular, molar mass, size, aggregation number, zeta potential, material density, number of oligonucleotide strands per particle, grafting density, and their relation to hallmark properties of spherical nucleic acids – biocompatibility, resistance against DNase I, cellular uptake without the need for transfection agents – are determined.

Asymmetric Cyclodextrin-Dimer-Involved Nanoassemblies by Selective Host–Guest Interactions: Concentration-Dependent Morphology Evolution and Light-Regulated Biomedical Applications

“…Polymeric assemblies including spherical, star-like, or worm-like nanoparticles, vesicles, or other complex structures could perform numerous applications in drug carriers or nanoreactors because of their unique characteristics and stability in a water environment. − The self-assembly of amphiphilic copolymers with both hydrophilic and hydrophobic building blocks have been studied extensively, and several ripe experiences have been summarized. However, besides amphiphilic copolymers, covalently linked organic–inorganic hybrid materials bearing organic polymer chains and inorganic units, such as carbon or metal nanoparticles, have attracted a lot of research interest. − Among inorganic nanobuilding blocks, polymer chain-modified fullerene C 60 has been widely investigated. − As one of the typical examples, a series of supramolecular nanoassemblies, including the core–shell structure, spherical nanoparticles (SNPs), and nanonetwork architectures could be constructed from isotactic (it-) and syndiotactic (st-) C 60 -end-capped poly­(methyl methacrylate)­s through adjusting the types of solvents and block ratios …”