title: Nebulized anionic guanidinylated O-carboxymethyl chitosan/N-2-hydroxypropyltimehyl ammonium chloride chitosan nanoparticles for siRNA pulmonary delivery: preparation, characterization and in vitro evaluation.
abstract: This study developed a pH-sensitive anionic system composed of guanidinylated O-carboxymethyl chitosan (GOCMCS) and N-2-hydroxypropyltimehyl ammonium chloride chitosan (N-2-HACC) for efficient siRNA delivery to the lungs following nebulization. About 16.8% of guanidine groups were incorporated into O-carboxymethyl chitosan (OCMCS) with the aid of O-methylisourea. Gel electrophoresis images demonstrated that siRNA was successfully encapsulated in nanoparticles ranging from 150 to 180 nm with zeta potential of about -17 mV. The nanoparticles containing GOCMCS existed superior transfection performance compared with their amino-based analogs. The evaluation in vitro revealed that nanoparticles were internalized into A549 cells by energy-dependent endocytosis, then achieved endosomal escape by direct transmembrane penetration of guanidine moieties as well as swelling behavior of nanoparticles due to the pH sensitivity of GOCMCS. The mRNA level of survivin gene was down-regulated to 6.9% using GOCMCS/N-2-HACC/siSurvivin NPs. The survivin siRNA mediated by nanoparticles caused 30% of cell growth inhibition and induced 19.45% of cell apoptosis, which was comparable to Lipofectamin2000. After nebulization of siRNA-loaded nanoparticles, the stability of siRNA was maintained and fine particle fractions were detected by two-stage impinger that accounted for more than 60%. These results suggested that GOCMCS/N-2-HACC nanoparticles possessed potential as safe and efficient carrier for siRNA pulmonary delivery.
authors.affiliation: a Department of Pharmacy , China Pharmaceutical University , Nanjing , PR China.
authors.forename: Suhui
authors.initials: S
authors.lastname: Ni
authors.affiliation: a Department of Pharmacy , China Pharmaceutical University , Nanjing , PR China.
authors.forename: Yuwen
authors.initials: Y
authors.lastname: Xie
authors.affiliation: a Department of Pharmacy , China Pharmaceutical University , Nanjing , PR China.
authors.forename: Yue
authors.initials: Y
authors.lastname: Tang
authors.affiliation: a Department of Pharmacy , China Pharmaceutical University , Nanjing , PR China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Liu
authors.affiliation: a Department of Pharmacy , China Pharmaceutical University , Nanjing , PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Chen
authors.affiliation: a Department of Pharmacy , China Pharmaceutical University , Nanjing , PR China.
authors.forename: Siyan
authors.initials: S
authors.lastname: Zhu
mesh_terms: D000072283:A549 Cells; D000838:Anions; D048271:Chitosan / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000737:chemistry; D005434:Flow Cytometry; D019791:Guanidine / Q000737:chemistry*; D006801:Humans; D066298:In Vitro Techniques; D008168:Lung / Q000378:metabolism*; D009330:Nebulizers and Vaporizers; D000644:Quaternary Ammonium Compounds / Q000008:administration & dosage* / Q000737:chemistry; D034741:RNA, Small Interfering / Q000008:administration & dosage*
chemical_list: D000838:Anions; C504164:O-carboxymethylchitosan; D000644:Quaternary Ammonium Compounds; D034741:RNA, Small Interfering; C576941:hydroxypropyltrimethyl ammonium chloride chitosan; D048271:Chitosan; D019791:Guanidine
keywords: Small interfering RNA; anionic nanoparticles; guanidinylation; nebulization; pH-sensitive