siRNA Nanoparticles for Ultra-Long Gene Silencing In Vivo.

Small interfering RNA (siRNA)-mediated gene silencing has shown prominent therapeutic effects in treating various diseases. However, adequate delivery and persistent gene silencing remain challenging. A nanoparticle-based delivery system which assembled by layering siRNAs between protease degradable polypeptides to show ultra-long gene silencing effect in vivo is developed. Gold nanoparticle is used as a scaffold for its unique properties including uniform size, biocompatibility, ready synthesis, and easy functionalization. A simple layer-by-layer fabrication approach, based on the electrostatic interaction between positively and negatively charged polymers, is applied to package the therapeutic siRNAs.