Tailored Design of Au Nanoparticle-siRNA Carriers Utilizing Reversible Addition - Fragmentation Chain Transfer Polymers

Stacey E. Kirkland-York, University of Southern Mississippi
Yilin Zhang, University of Southern Mississippi
Adam E. Smith, University of Southern Mississippi
Adam W. York, University of Southern Mississippi
Faqing Huang, University of Southern Mississippi
Charles L. McCormick, University of Southern Mississippi

Abstract

The facile synthesis of polymer-stabilized Au nanoparticles (AuNPs) capable of forming neutral, sterically stable complexes with small interfering RNA (siRNA) is reported. The amine-containing cationic block of poly(N-2-hydroxypropyl methacrylamide(70)-Nock-N-[3-(dimethylamino)propyl] methacrylamide(24)) [P(HPMA(70)-b-DMAPMA(24))] was utilized to promote the in situ reduction of Au(3+) to AuNPs and subsequently bind small interfering RNA, while the nonimmunogenic, hydrophilic block provided steric stabilization. The ratio of [DMAPMA](0)/[Au(3+)](0) utilized in the reduction reaction was found to be critical to the production of polymer-stabilized AuNPs capable of complexing siRNA. Significant protection (similar to 100 times) against nucleases was demonstrated by enzymatic tests, while gene down-regulation experiments indicated successful delivery of siRNA to cancerous cells.