title: Chitosan derivatives for gene transfer: effect of phosphorylcholine and diethylaminoethyl grafts on the in vitro transfection efficiency.
abstract: The purpose of this work was to improve the functional properties of chitosan for gene transfer by inserting phosphorylcholine (PC) and diethylaminoethyl (DEAE) groups into the main chain. A series of derivatives containing increasing contents of DEAE and a fixed content of PC groups were synthesized and characterized, aiming to evaluate the effect of these groups on the nanoparticles' properties and the in vitro transfection efficiency. The derivatives were soluble at physiological pH levels and all derivatives were less cytotoxic than the control, the lipid lipofectamine. The obtained derivatives complexed pDNA into nanoparticles with smaller sizes and higher zeta potentials than plain chitosan. The in vitro transfection was performed with nanoparticles prepared at pH 6.3 and 7.4 and the results showed that nanoparticles prepared with derivatives containing 20% of PC groups (PC18-CH) and high degrees of substitution by DEAE (PC20-CH-DEAE100, CH-DEAE80, CH-DEAE100) displayed the better transfection efficiencies in HeLa cells, reaching relative values comparable to lipofectamine. The most effective derivative, PC18CH, was selected for complexation with siRNA and its complexes demonstrated an in vitro knockdown efficiency highly dependent on the N/P ratio. Our combined results indicated that, by means of controlled modifications, the limitations of chitosan can be overcome to obtain more effective carriers based on chitosan, and the derivatives here studied hold potential for in vivo studies.
authors.affiliation: a Department of Physics , IBILCE, São Paulo State University - UNESP , São José do Rio Preto , São Paulo , Brazil.|b Orthopedic Research Laboratory , Hôpital du Sacré-Cœur de Montréal, Université de Montréal , Montréal , Canada.
authors.forename: Isadora Pfeifer Dalla
authors.initials: IP
authors.lastname: Picola
authors.affiliation: b Orthopedic Research Laboratory , Hôpital du Sacré-Cœur de Montréal, Université de Montréal , Montréal , Canada.
authors.forename: Qin
authors.initials: Q
authors.lastname: Shi
authors.affiliation: b Orthopedic Research Laboratory , Hôpital du Sacré-Cœur de Montréal, Université de Montréal , Montréal , Canada.
authors.forename: Júlio Cesar
authors.initials: JC
authors.lastname: Fernandes
authors.affiliation: c Department of Chemistry and Environmental Sciences , IBILCE, São Paulo State University - UNESP , São José do Rio Preto , São Paulo , Brazil.
authors.forename: Maicon Segalla
authors.initials: MS
authors.lastname: Petrônio
authors.affiliation: c Department of Chemistry and Environmental Sciences , IBILCE, São Paulo State University - UNESP , São José do Rio Preto , São Paulo , Brazil.
authors.forename: Aline Margarete Furuyama
authors.initials: AM
authors.lastname: Lima
authors.affiliation: c Department of Chemistry and Environmental Sciences , IBILCE, São Paulo State University - UNESP , São José do Rio Preto , São Paulo , Brazil.
authors.forename: Vera Aparecida
authors.initials: VA
authors.lastname: de Oliveira Tiera
authors.affiliation: c Department of Chemistry and Environmental Sciences , IBILCE, São Paulo State University - UNESP , São José do Rio Preto , São Paulo , Brazil.
authors.forename: Marcio José
authors.initials: MJ
authors.lastname: Tiera
mesh_terms: D048271:Chitosan / Q000737:chemistry* / Q000633:toxicity; D004247:DNA / Q000737:chemistry / Q000235:genetics; D004337:Drug Carriers / Q000737:chemistry* / Q000633:toxicity; D004983:Ethanolamines / Q000737:chemistry*; D020868:Gene Silencing; D006367:HeLa Cells; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry; D010316:Particle Size; D010767:Phosphorylcholine / Q000737:chemistry*; D010957:Plasmids / Q000235:genetics; D034741:RNA, Small Interfering / Q000737:chemistry / Q000235:genetics; D014162:Transfection
chemical_list: D004337:Drug Carriers; D004983:Ethanolamines; D034741:RNA, Small Interfering; D010767:Phosphorylcholine; D004247:DNA; D048271:Chitosan; C007369:2-diethylaminoethanol
keywords: Chitosan; DNA; derivatives; gene therapy; nanoparticles; phosphorylcholine; polyplexes; siRNA