Janus Base Nanopieces for Intracellular Delivery and Endosomal Escape

Y. Chen
University of Connecticut,,
United States

Keywords: nanopieces, Janus base nanotubes, JBNT, gene


RNA interference (RNAi) offers great potential to silence a single gene to treat genetic disorders and infectious diseases. However, small interfering RNA (siRNA) needs to be delivered into human cells but limited due to their negative surface charge, large molecule weight, and enzyme degradable structure. A major limitation of RNAi therapeutics is the endosomal entrapment of the delivered siRNA. Lipid nanoparticles (LNPs) can efficiently deliver RNA cargos into various types of cells, but they are limited by poor endosomal escape ability so that a majority of delivered siRNAs are not functional; cationic polymers can escape from endosomes; however, the presence of a covalent bond in their structure causes low biodegradability and high cytotoxicity. In this study, we developed a new family of delivery vehicles called Nanopieces (NPs) based on non-covalent DNA-inspired Janus base nanotubes (JBNTs), which combine their advantages in endosomal escape and low toxicity. JBNTs are comprised of self-assembled supramolecular structures which are further broken down into DNA base pairs (Fig. 1A). The hollow channels formed by these nanotubes are ideal for drug loading and the six-member rosette comprised of hydrogen bonding is essential for its low cytotoxicity profile. By controlled assembly between the therapeutic cargos with JBNT solution, long segmented Nanopieces are synthesized. They can be further separated via a regulated sonication process. Nanopieces with formulations were assembled and their material properties were studied using dynamic light scattering (DLS) and Zeta potential measurements. Their morphological characteristics and distributions were analyzed by transmission electron microscopy (TEM) imaging. Results of this study provide in-depth characterizations of these NPs along with evaluating their abilities of intracellular delivery and endosomal escape.