title: Evaluation of Chitosan-Tripolyphosphate Nanoparticles as a p-shRNA Delivery Vector: Formulation, Optimization and Cellular Uptake Study.
abstract: Polysaccharides (especially chitosan) have recently attracted much attention as gene therapy delivery vehicles for their unique properties such as biocompatibility, biodegradability, low toxicity, and controlled release. Nanoparticles have strong potential as a carrier of plasmid short hairpin RNA (p-shRNA). This study aimed to find the optimum conditions for obtaining Chitosan/triphosphate (TPP)/p-shRNA nanoparticles by the ionic gelation method, and investigating the cellular uptake of the optimized nanoparticles. After applying the central composite design of response surface methodology (RSM), the optimum conditions for preparation of nanoparticles with small size and high loading efficiency were: chitosan/TPP ratio = 10, pH = 5.5 and N/P ratio = 11. The resulting nanoparticles had an average size of 172.8 ± 7 nm and loading efficiency of 71.5 ± 5%. SEM images showed spherical and smooth nanoparticles. The nanoparticles complexed with p-shRNA and may protect it against nuclease digestion. Cytotoxicity studies with HeLa and PC3 human cancer cells demonstrated that chitosan/TPP nanoparticles had low toxicity. Cellular uptake studies using HeLa cells showed that the nanoparticles entered the cells (cellular uptake) and delivered DNA, probably due to their favorable Zeta potential (approximately +28 mV) and small size.
authors.affiliation: Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115, Iran; Department of Dermatology, Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston MA, 02114, USA.
authors.forename: Mahdi
authors.initials: M
authors.lastname: Karimi
authors.affiliation: Department of Dermatology, Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston MA, 02114, USA; Department of Dermatology, Semmelweis University School of Medicine, Budapest, 1085, Hungary.
authors.forename: Pinar
authors.initials: P
authors.lastname: Avci
authors.affiliation: Biotechnology Group, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, 14115, Iran.
authors.forename: Mohsen
authors.initials: M
authors.lastname: Ahi
authors.affiliation: Biotechnology Group, Faculty of Chemical Engineering, Tarbiat Modares University, Tehran, 14115, Iran.
authors.forename: Tarane
authors.initials: T
authors.lastname: Gazori
authors.affiliation: Department of Dermatology, Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston MA, 02114, USA; Harvard-MIT Division of Health Sciences and Technology, Cambridge, MA, 02139, USA.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Hamblin
authors.affiliation: Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115, Iran; Department of Biophysics, Faculty of Biological Sciences, Tarbiat Modares University, Tehran, 14115, Iran.
authors.forename: Hossein
authors.initials: H
authors.lastname: Naderi-Manesh
keywords: Cellular Uptake; Chitosan; Gene Delivery; Nanoparticle; Response Surface Methodology (RSM); p-shRNA