Alex M Chen et al 2006 Nanotechnology 17 5449 doi:10.1088/0957-4484/17/21/027
Alex M Chen1, Latha M Santhakumaran2, Sandhya K Nair2, Peter S Amenta3,4, Thresia Thomas4,5,6, Huixin He1,7 and T J Thomas2,6,7
Show affiliationsWe studied the efficacy of five generations of polypropyleneimine (PPI) dendrimer to provoke nanostructure formation from a 21-nucleotide antisense oligodeoxynucleotide (ODN). Nanostructure formation was observed with all generations of dendrimer by light scattering and microscopic techniques. The efficacy of the dendrimers increased with generation number. Atomic force microscopy (AFM) was used to study the morphology of the structures at different condensation stages. Based on the observed nanostructures, we propose a zipping condensation mechanism, which is very different from the condensation pathways of high molecular weight DNA polymers. Electron microscopy showed the presence of toroidal nanoparticles. Confocal microscopic analysis showed that the nanostructures formed with G-4 and G-5 dendrimers could undergo facile cellular uptake in a breast cancer cell line, MDA-MB-231, whereas nanostructures formed with G-1 to G-3 dendrimers lacked this ability. Nanoparticles formed with G-1 to G-3 dendrimers showed significantly lower zeta potential (5.2–6.5 mV) than those (12–18 mV) of particles formed with G-4 and G-5 dendrimers. These results show that the structure and charge density of the dendrimers are important in ODN nanoparticle formation and cellular transport and that G-4 and G-5 dendrimers are useful in cellular delivery of antisense ODN.
87.85.Qr Nanotechnologies-design
87.64.Dz Scanning tunneling and atomic force microscopy
Issue 21 (14 November 2006)
Received 13 July 2006, in final form 21 September 2006
Published 20 October 2006
Alex M Chen et al 2006 Nanotechnology 17 5449
Christian Marois et al 2007 ApJ 654 L151
P. Montañés-Rodriguez et al. 2005 ApJ 629 1175
A. W. Shafter and K. A. Misselt 2006 ApJ 644 1104
Y. R. Fernández et al. 2006 The Astronomical Journal 132 1354
M Jura 2008 The Astronomical Journal 135 1785
Ji-Wei Xie and Ji-Lin Zhou 2009 ApJ 698 2066
D Grossman et al 2008 New J. Phys. 10 023036
M. V. Simkin and V. P. Roychowdhury 2008 EPL 82 28006
F. H. Cheng et al 1997 ApJ 484 L149