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Low molecular weight chitosan nanoparticulate system at low N:P ratio for nontoxic polynucleotide delivery

Abderrazzak Merzouki, Mohamad Alameh, Diogo DeJesus, Myriam Jean, Vincent Darras, Marc Thibault, Marc Lavertu and Michael D. Buschmann

Article (2012)

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Chitosan, a natural polymer, is a promising system for the therapeutic delivery of both plasmid DNA and synthetic small interfering RNA. Reports attempting to identify the optimal parameters of chitosan for synthetic small interfering RNA delivery were inconclusive with high molecular weight at high amine-to-phosphate (N:P) ratios apparently required for efficient transfection. Here we show, for the first time, that low molecular weight chitosan (LMW-CS) formulations at low N:P ratios are suitable for the in vitro delivery of small interfering RNA. LMW-CS nanoparticles at low N:P ratios were positively charged (zeta-potential similar to 20 mV) with an average size below 100 nm as demonstrated by dynamic light scattering and environmental scanning electron microscopy, respectively. Nanoparticles were spherical, a shape promoting decreased cytotoxicity and enhanced cellular uptake. Nanoparticle stability was effective for at least 20 hours at N:P ratios above two in a slightly acidic pH of 6.5. At a higher basic pH of 8, these nanoparticles were unravelled due to chitosan neutralization, exposing their polynucleotide cargo. Cellular uptake ranged from 50% to 95% in six different cell lines as measured by cytometry. Increasing chitosan molecular weight improved nanoparticle stability as well as the ability of nanoparticles to protect the oligonucleotide cargo from nucleases at supraphysiological concentrations. The highest knockdown efficiency was obtained with the specific formulation 92-10-5 that combines sufficient nuclease protection with effective intracellular release. This system attained &gt;70% knockdown of the messenger RNA, similar to commercially available lipoplexes, without apparent cytotoxicity. Contrary to previous reports, our data demonstrate that LMW-CS at low N:P ratios are efficient and nontoxic polynucleotide delivery systems capable of transfecting a plethora of cell lines.

Uncontrolled Keywords

ApoB; RecQL1; chitosan; gene silencing; nonviral delivery system; siRNA; Animals; Cell Line; Cell Survival; Chitosan; Drug Delivery Systems; Flow Cytometry; Gene Silencing; HEK293 Cells; Hep G2 Cells; Histocytochemistry; Humans; Hydrogen-Ion Concentration; Mice; Microscopy, Confocal; Molecular Weight; Nanoparticles; Particle Size; Plasmids; RNA, Small Interfering; Transfection; RNA, Small Interfering; Chitosan

Subjects: 1800 Chemical engineering > 1800 Chemical engineering
3750 Polymer chemistry > 3754 Biopolymers
Department: Department of Chemical Engineering
Funders: CRSNG / NSERC, Groupe de recherche en sciences et technologies biomédicales (FRSQ)
PolyPublie URL: https://publications.polymtl.ca/3420/
Journal Title: International Journal of Nanomedicine (vol. 7)
Publisher: Dove Press Ltd
DOI: 10.2147/ijn.s26571
Official URL: https://doi.org/10.2147/ijn.s26571
Date Deposited: 03 Dec 2018 16:36
Last Modified: 01 Nov 2023 12:59
Cite in APA 7: Merzouki, A., Alameh, M., DeJesus, D., Jean, M., Darras, V., Thibault, M., Lavertu, M., & Buschmann, M. D. (2012). Low molecular weight chitosan nanoparticulate system at low N:P ratio for nontoxic polynucleotide delivery. International Journal of Nanomedicine, 7, 1399-1414. https://doi.org/10.2147/ijn.s26571


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