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Evaluation of Polymeric Gene Delivery Nanoparticles by Nanoparticle Tracking Analysis and High-throughput Flow Cytometry
Published on: March 1, 2013
Gene delivery using dimethyldidodecylammonium bromide-coated PLGA nanoparticles
François Fay1, Derek J Quinn, Brendan F Gilmore
1School of Pharmacy, Queens University of Belfast, Belfast, UK.
Biomaterials
|February 27, 2010
Summary
This study presents a novel poly(lactic-co-glycolic acid) (PLGA) nanoparticle formulation for effective intracellular DNA delivery. Cationic DMAB-coated nanoparticles enhance gene transfection and escape endosomes with reduced cytotoxicity.
Area of Science:
- Biomaterials Science
- Nanotechnology
- Gene Delivery Systems
Background:
- Effective intracellular delivery of plasmid DNA is crucial for gene therapy.
- Poly(lactic-co-glycolic acid) (PLGA) nanoparticles offer a promising platform for drug and gene delivery.
- Overcoming endosomal entrapment remains a key challenge for efficient gene transfection.
Purpose of the Study:
- To develop and characterize a novel PLGA nanoparticle formulation for enhanced intracellular plasmid DNA delivery.
- To investigate the role of cationic surface modification in promoting endosomal escape and improving transfection efficiency.
- To compare the efficacy and cytotoxicity of different cationic surfactants (CTAB vs. DMAB) for nanoparticle functionalization.
Main Methods:
- PLGA nanoparticles encapsulating plasmid DNA were fabricated using a combination of salting out and emulsion-evaporation techniques.
- Surface cationic charge was introduced using cetyl trimethylammonium bromide (CTAB) and dimethyldidodecylammonium bromide (DMAB) to facilitate endosomal escape.
- Nanoparticle characterization included size, zeta potential, and morphology analysis (TEM).
- Cell viability assays and fluorescence microscopy were employed to assess cytotoxicity and intracellular localization, respectively.
- Transfection efficiency was evaluated using a GFP reporter plasmid.
Main Results:
- Monodispersed PLGA nanoparticles (approx. 240 nm) successfully encapsulated plasmid DNA.
- Cationic surface modification with CTAB and DMAB increased zeta potential, indicating successful charge introduction.
- DMAB-coated nanoparticles demonstrated significantly lower cytotoxicity compared to CTAB-coated nanoparticles at equivalent positive zeta potentials.
- DMAB-coated nanoparticles successfully evaded the endosomal lumen and localized in the cytosol.
- DMAB-coated PLGA nanoparticles significantly improved transfection efficiencies for the GFP reporter plasmid compared to non-modified particles.
Conclusions:
- The developed PLGA nanoparticle formulation offers an effective strategy for intracellular plasmid DNA delivery.
- DMAB-mediated cationic coating promotes endosomal escape and enhances gene transfection efficiency with reduced cytotoxicity.
- These DMAB-coated PLGA nanoparticles hold potential for applications in targeted gene therapies.
