Combinatorial siRNA Polyplexes for Receptor Targeting

  • Dian-Jang Lee
  • Ernst WagnerEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1974)


As synthetic small interfering RNA (siRNA) against antitumoral gene targets show promise for cancer treatment, different siRNA delivery systems have sparkled intense investigations. To develop tumor-specific carriers for cytosolic and systemic siRNA delivery, our laboratory has recently generated folate-conjugated targeted combinatorial siRNA polyplexes based on sequence-defined oligomer platform compatible with solid-phase-supported synthesis. These polyplexes presented efficient siRNA-mediated gene silencing in folate receptor-expressing tumors in vitro and in vivo. In this chapter, we provide a brief background on the formulation design and detailed protocols to evaluate polyplex formation, gene silencing efficiency, and receptor-directed cell killing in cancer cells using targeted combinatorial siRNA polyplexes.


siRNA delivery Gene silencing Polyplex Receptor targeting 



The work presented in this article was supported by German Research Foundation (DFG) grant SFB1032 (Project B4) and German Excellence Cluster Nanosystems Initiative Munich.


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Copyright information

© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of Pharmacy, Center for NanoScienceLudwig-Maximilians-Universität MünchenMunichGermany
  2. 2.Nanosystems Initiative Munich (NIM)MunichGermany

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