Investigation of the structural organization of cationic nanoemulsion/antisense oligonucleotide complexes.
Atomic force microscopy image analysis and energy dispersive X-ray diffraction experiments were used to investigate the structural organization of cationic nanoemulsion/oligonucleotide complexes. Oligonucleotides targeting topoisomerase II gene were adsorbed on cationic nanoemulsions obtained by means of spontaneous emulsification procedure. Topographical analysis by atomic force microscopy allowed the observation of the nanoemulsion/oligonucleotide complexes through three-dimensional high-resolution images. Flattening of the oil droplets was observed, which was reduced in the complexes obtained at high amount of adsorbed oligonucleotides. In such conditions, complexes exhibit droplet size in the 600nm range. The oligonucleotides molecules were detected on the surface of the droplets, preventing their fusion during aggregation. A lamellar structure organization was identified by energy dispersive X-ray diffraction experiments. The presence of the nucleic acid molecules led to a disorganization of the lipid arrangement and an expansion in the lattice spacing, which was proportional to the amount of oligonucleotides added.
Programa de Pós-graduação em Ciências Farmacêuticas da Universidade Federal do Rio Grande do Sul (UFRGS), Av. Ipiranga 2752, 90610-000 Porto Alegre, Brazil.
Fernanda
F
Bruxel
José Mario Carneiro
JM
Vilela
Margareth Spangler
MS
Andrade
Ângelo
Â
Malachias
Carlos A
CA
Perez
Rogério
R
Magalhães-Paniago
Mônica Cristina
MC
Oliveira
Helder F
HF
Teixeira
D002412:Cations; D004250:DNA Topoisomerases, Type II / Q000235:genetics; D016054:DNA, Protozoan / Q000235:genetics; D016503:Drug Delivery Systems; D004655:Emulsions; D018390:Gene Targeting; D018625:Microscopy, Atomic Force; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D016376:Oligonucleotides, Antisense / Q000008:administration & dosage / Q000737:chemistry* / Q000235:genetics; D010963:Plasmodium falciparum / Q000201:enzymology / Q000235:genetics; D014961:X-Ray Diffraction
D002412:Cations; D016054:DNA, Protozoan; D004655:Emulsions; D016376:Oligonucleotides, Antisense; D004250:DNA Topoisomerases, Type II
Antisense oligonucleotides; Atomic force microscopy; Cationic lipids; Energy dispersive X-ray diffraction; Nanoemulsions; Phospholipids; X-ray diffractometry