title: Effect of cationic lipid composition on properties of oligonucleotide/emulsion complexes: Physico-chemical and release studies.
abstract: This paper describes the influence of cationic lipid composition on physico-chemical properties of complexes formed between oligonucleotides (ON) and cationic emulsions. Formulations containing medium chain triglycerides, egg lecithin, increasing amounts of either oleylamine (OA) or 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP), and water were prepared by a spontaneous emulsification procedure. ON adsorption on emulsions was evidenced by the inversion of the zeta-potential, the increase in droplet size, and the morphology of the oil droplet examined through transmission electron microscopy. Adsorption isotherms showed a higher amount of ON adsorbed on emulsions containing DOTAP when compared to emulsions containing OA. In a final step, the role of the main parameters, which may in fact influence the ON release rate from emulsions, was investigated. ON were progressively released from emulsions with an increase in dilution ratio and remained quite similar for both OA and DOTAP emulsions over time. Conversely, the effect of the cationic lipid composition was observed upon increasing the charge ratio of complexes. ON release at a same charge ratio was lower from emulsions containing DOTAP (bearing dioleyl chains) than from those containing OA (bearing monoleyl chain).
authors: Programa de Pós-graduação em Ciências Farmacêuticas da Universidade Federal do Rio Grande do Sul (UFRGS), Av. Ipiranga 2752, 90610-000 Porto Alegre, RS, Brazil.
authors: Erico
authors: E
authors: Martini
authors: Elias
authors: E
authors: Fattal
authors: Mônica Cristina
authors: MC
authors: de Oliveira
authors: Helder
authors: H
authors: Teixeira
mesh_terms: D000327:Adsorption; D000588:Amines / Q000737:chemistry; D002412:Cations; D004655:Emulsions; D005229:Fatty Acids, Monounsaturated / Q000737:chemistry; D018014:Gene Transfer Techniques; D054709:Lecithins / Q000737:chemistry; D008055:Lipids / Q000737:chemistry*; D015394:Molecular Structure; D009841:Oligonucleotides / Q000737:chemistry*; D010316:Particle Size; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012995:Solubility; D055672:Static Electricity; D013997:Time Factors; D014280:Triglycerides / Q000737:chemistry; D014867:Water / Q000737:chemistry
chemical_list: D000588:Amines; D002412:Cations; D004655:Emulsions; D005229:Fatty Acids, Monounsaturated; D054709:Lecithins; D008055:Lipids; D009841:Oligonucleotides; D000644:Quaternary Ammonium Compounds; D014280:Triglycerides; D014867:Water; C070046:1,2-dioleoyloxy-3-(trimethylammonium)propane; C008703:oleylamine