title: DOTAP functionalizing single-walled carbon nanotubes as non-viral vectors for efficient intracellular siRNA delivery.
abstract: BACKGROUND
  Functionalized single-walled carbon nanotubes (SWNT) with 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) were used as novel and more convenient carriers of small interfering RNA (siRNA).
  
  
  OBJECTIVE
  To utilize the unique capability of SWNT to be easily modified by functional groups and readily internalized by mammalian cells to bind, condense, stabilize siRNA and enhance its transfection efficiency.
  
  
  METHODS
  After SWNT were non-covalently functionalized by cationic DOTAP (SWNT-DOTAP), siRNA interacted with SWNT-DOTAP via static electricity (SWNT-DOTAP/siRNA). Subsequently, the size, zeta potential and morphology of SWNT-DOTAP/siRNA were analyzed. The optimal compression ratio and stability of siRNA were assessed by agarose gel electrophoresis. Furthermore, in prostate carcinoma PC-3 cells, RT-PCR, flow cytometry and sulforhodamine B assays were used to evaluate the silencing activity, transfection efficiency and cell proliferation, respectively.
  
  
  CONCLUSIONS
  The characteristics of SWNT-DOTAP, i.e. an average size of 194.49 nm, a zeta potential of 45.16 mV and lower cytotoxicity than Lipofectamine 2000, indicated that this vector was suitable for siRNA delivery. Moreover, after interaction with SWNT-DOTAP, siRNA of human telomerase reverse transcriptase was bound, condensed and stabilized. In PC-3 cells, SWNT-DOTAP/siRNA exhibited 82.6% silencing activity and 92% transfection efficiency. Furthermore, the complexes inhibited cell proliferation by 42.1%.
  
  
  CONCLUSIONS
  SWNT-DOTAP may be a promising siRNA delivery vector for gene-based therapeutic applications in cancer.
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Haixia
authors.initials: H
authors.lastname: Li
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Yongwei
authors.initials: Y
authors.lastname: Hao
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .|b Department of pharmacy , the First Affiliated Hospital of Xinxiang Medical University , Xinxiang 453100 , China.
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Shasha
authors.initials: S
authors.lastname: Jia
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Yali
authors.initials: Y
authors.lastname: Wang
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Lijia
authors.initials: L
authors.lastname: Yang
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Yun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: a School of Pharmaceutical Sciences, Zhengzhou University , Zhengzhou 450002 , China .
authors.forename: Zhenzhong
authors.initials: Z
authors.lastname: Zhang
mesh_terms: D002412:Cations / Q000737:chemistry; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004337:Drug Carriers / Q000737:chemistry*; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry*; D020868:Gene Silencing / Q000187:drug effects; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000008:administration & dosage*; D006801:Humans; D008055:Lipids / Q000008:administration & dosage / Q000737:chemistry; D037742:Nanotubes, Carbon / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D034741:RNA, Small Interfering / Q000008:administration & dosage*; D014162:Transfection / Q000379:methods
chemical_list: D002412:Cations; D004337:Drug Carriers; D005229:Fatty Acids, Monounsaturated; D008055:Lipids; C086724:Lipofectamine; D037742:Nanotubes, Carbon; D000644:Quaternary Ammonium Compounds; D034741:RNA, Small Interfering; C070046:1,2-dioleoyloxy-3-(trimethylammonium)propane
keywords: Cancer therapy; gene silencing; non-viral vector; siRNA; single-walled carbon nanotubes