title: Gene delivery using dendrimer-entrapped gold nanoparticles as nonviral vectors.
abstract: Development of highly efficient nonviral gene delivery vectors still remains a great challenge. In this study, we report a new gene delivery vector based on dendrimer-entrapped gold nanoparticles (Au DENPs) with significantly higher gene transfection efficiency than that of dendrimers without AuNPs entrapped. Amine-terminated generation 5 poly(amidoamine) (PAMAM) dendrimers (G5.NH(2)) were utilized as templates to synthesize AuNPs with different Au atom/dendrimer molar ratios (25:1, 50:1, 75:1, and 100:1, respectively). The formed Au DENPs were used to complex two different pDNAs encoding luciferase (Luc) and enhanced green fluorescent protein (EGFP), respectively for gene transfection studies. The Au DENPs/pDNA polyplexes with different N/P ratios and compositions of Au DENPs were characterized by gel retardation assay, light scattering, zeta potential measurements, and atomic force microscopic imaging. We show that the Au DENPs can effectively compact the pDNA, allowing for highly efficient gene transfection into the selected cell lines as demonstrated by both Luc assay and fluorescence microscopic imaging of the EGFP expression. The transfection efficiency of Au DENPs with Au atom/dendrimer molar ratio of 25:1 was at least 100 times higher than that of G5.NH(2) dendrimers without AuNPs entrapped at the N/P ratio of 2.5:1. The higher gene transfection efficiency of Au DENPs is primarily due to the fact that the entrapment of AuNPs helps preserve the 3-dimensional spherical morphology of dendrimers, allowing for more efficient interaction between dendrimers and DNA. With the less cytotoxicity than that of G5.NH(2) dendrimers demonstrated by thiazoyl blue tetrazolium bromide assay and higher gene transfection efficiency, it is expected that Au DENPs may be used as a new gene delivery vector for highly efficient transfection of different genes for various biomedical applications.
authors.affiliation: State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, Shanghai 201620, People's Republic of China.
authors.forename: Yuebin
authors.initials: Y
authors.lastname: Shan
authors.forename: Ting
authors.initials: T
authors.lastname: Luo
authors.forename: Chen
authors.initials: C
authors.lastname: Peng
authors.forename: Ruilong
authors.initials: R
authors.lastname: Sheng
authors.forename: Amin
authors.initials: A
authors.lastname: Cao
authors.forename: Xueyan
authors.initials: X
authors.lastname: Cao
authors.forename: Mingwu
authors.initials: M
authors.lastname: Shen
authors.forename: Rui
authors.initials: R
authors.lastname: Guo
authors.forename: Helena
authors.initials: H
authors.lastname: Tomás
authors.forename: Xiangyang
authors.initials: X
authors.lastname: Shi
mesh_terms: D000588:Amines / Q000737:chemistry; D000818:Animals; D019556:COS Cells; D016923:Cell Death; D002470:Cell Survival; D002522:Chlorocebus aethiops; D050091:Dendrimers / Q000737:chemistry*; D004587:Electrophoresis, Agar Gel; D024202:Electrophoretic Mobility Shift Assay; D004705:Endocytosis; D005434:Flow Cytometry; D018014:Gene Transfer Techniques; D005822:Genetic Vectors / Q000235:genetics*; D006046:Gold / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D057446:Hydrodynamics; D008156:Luciferases / Q000378:metabolism; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D018625:Microscopy, Atomic Force; D008856:Microscopy, Fluorescence; D010316:Particle Size; D055672:Static Electricity; D014162:Transfection; D014780:Viruses / Q000235:genetics
chemical_list: D000588:Amines; D050091:Dendrimers; D006046:Gold; D008156:Luciferases