Pharmaceutical Research

, Volume 26, Issue 3, pp 657–666 | Cite as

Efficient siRNA Delivery with Non-viral Polymeric Vehicles

Expert Review


Sequence-specific gene silencing using small interfering RNA (siRNA) provides a potent and specific method for gene expression, thus is now being evaluated in clinical trials as a novel therapeutic strategy. As a results, there has been a significant surge of interest in the application of siRNA in therapeutics as a means of silencing the specific gene function. However, for siRNA technology to be valuable and effective, the development of efficient siRNA delivery strategy is essential for improving biological activities such as stability, cellular uptake, sequence-specificity, devoid of nonspecific knockdown and toxic side effects. Accordingly, a number of delivery systems, both viral and nonviral, have been reported and some of them successfully used for the introduction of siRNA into cells both in vitro and in vivo. Here, we discuss the current understanding of synthetic siRNA delivery mechanism and strategies of siRNA delivery by non-viral polymeric vehicles which are currently used in vitro and in vivo.


cationic polymer gene therapy polymeric carrier small interfering RNA 



This study was supported by a grant of the Korea Healthcare technology R&D Project, Ministry of Health and Welfare, Republic of Korea (A080919), the Nano-Biotechnology Project (Regenomics), Ministry of Science and Technology, Republic of Korea (850-20080090), and a grant from the National Institute of Health, USA (NIH, CA 107070).


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  1. 1.Department of ChemistryPohang University of Science and TechnologyPohangSouth Korea
  2. 2.Center for Controlled Chemical Delivery, Department of Pharmaceutics and Pharmaceutical ChemistryUniversity of UtahSalt Lake CityUSA

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