Article

Chitosan nanoparticles for plasmid DNA delivery: effect of chitosan molecular structure on formulation and release characteristics.

Department of Pharmaceutical Technology, Faculty of Pharmacy, Ankara University, Ankara, Turkey.
Drug Delivery (impact factor: 1.46). 11(2):107-12. DOI:10.1080/10717540490280705 pp.107-12
Source: PubMed

ABSTRACT Chitosan can be useful as a nonviral vector for gene delivery. Although there are several reports to form chitosan-pDNA particles, the optimization and effect on transfection remain insufficient. The chitosan-pDNA nanoparticles were formulated using complex coacervation and solvent evaporation techniques. The important parameters for the encapsulation efficiency were investigated, including molecular weight and deacetylation degree of chitosan. We found that encapsulation efficiency of pDNA is directly proportional with deacetylation degree, but there is an inverse proportion with molecular weight of chitosan. DNA-nanoparticles in the size range of 450-820 nm depend on the formulation process. The surface charge of the nanoparticles prepared with complex coacervation method was slightly positive with a zeta potential of +9 to +18 mV; nevertheless, nanoparticles prepared with solvent evaporation method had a zeta potential approximately +30 mV. The pDNA-chitosan nanoparticles prepared by using high deacetylation degree chitosan having 92.7%, 98.0%, and 90.4% encapsulation efficiency protect the encapsulated pDNA from nuclease degradation as shown by electrophoretic mobility analysis. The release of pDNA from the formulation prepared by complex coacervation was completed in 24 hr whereas the formulation prepared by evaporation technique released pDNA in 96 hr, but these release profiles are not statistically significant compared with formulations with similar structure (p > .05). According to the results, we suggest nanoparticles have the potential to be used as a transfer vector in further studies.

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Keywords

90.4% encapsulation efficiency
 
chitosan-pDNA nanoparticles
 
complex coacervation
 
complex coacervation method
 
deacetylation degree chitosan
 
electrophoretic mobility analysis
 
encapsulation efficiency
 
evaporation technique
 
form chitosan-pDNA particles
 
formulation process
 
molecular weight
 
nonviral vector
 
nuclease degradation
 
pDNA-chitosan nanoparticles
 
release profiles
 
size range
 
solvent evaporation method
 
solvent evaporation techniques
 
transfer vector
 
zeta potential