Kinetically Interlocking Multiple-Units Polymerization of DNA Double Crossover and Its Application in Hydrogel Formation.

A novel kinetically interlocking multiple-units (KIMU) supramolecular polymerization system with DNA double crossover backbone is designed. The rigidity of DX endows the polymer with high molecular weight and stability. The observed concentration of the formed polymers is insensitive and stable under ultralow monomer concentration owing to the KIMU interactions, in which multiple noncovalent interactions are connected by the phosphodiester bonds. Furthermore, a pH-responsive DNA supramolecular hydrogel is constructed by introducing a half i-motif domain into the DNA monomer. The rigidity of DNA polymer endows the hydrogel with high mechanical strength and low gelation concentration. This study enriches the KIMU strategy and offers a simple but effective way to fabricate long and stable supramolecular polymers by balancing the reversibility and stability. It also shows great potentials to construct next generation of smart materials, such as DNA nanostructures, DNA motors, and DNA hydrogels.

Preparing liposomes through frame guided assembly with high-loading functional nucleic acids.

Recently, a frame guided assembly (FGA) has been demonstrated as a robust tool to prepare liposomes with customized morphologies. However, the potential application of FGA liposomes in delivering nucleic acid drugs is still limited by the low payload. In this study, by systemically investigating the correlation between the leading hydrophobic group (LHG) density and the initial detergent concentration, it has been demonstrated that frames with a low LHG density, which may facilitate the increase of the load of the nucleic acid drug, could be guided to form liposomes at low initial detergent concentrations. By capitalizing on this phenomenon, FGA liposomes with a high loading of ASO/siRNA have been successfully prepared and applied to treat pathogenic genes.