Preparation, characterization, and evaluation of chitosan-based nanoparticles as CpG ODN carriers

Abstract

Chitosan-based particles are desirable materials for drug delivery because of their muco-adhesiveness in tissues, biocompatibility, low toxicity and effectiveness in antigen transport. It is still a challenge to prepare chitosan-based particles with high stability and by an effective method. Here we developed chitosan-based nanoparticles for the delivery of toll-like receptor 9 ligands, cytosine-phosphate-guanine oligodeoxynucleotides (CpG ODNs), which can induce the change from Th-2 type to Th-1 type immune response. Because of the low tolerance to DNase and less uptake into the cells of the free CpG ODNs, the development of positively charged carriers is necessary for the effective delivery of CpG ODNs into immune cells. Chitosan nanoparticles were prepared by ionic gelation, and the nanoparticles size and surface charge were measured by dynamic light spectroscopy and zeta potential analyzer, respectively. The synthesized chitosan nanoparticles showed two dispersion peaks, at 196 ± 29 nm and 1.33 ± 0.36 lm, with a zeta potential of þ3.3 ± 0.4 mV. The toxicity of the chitosan nanoparticles to murine RAW264 macrophages was measured by formazan dye assay utilizing the water-soluble tetrazolium salt WST-8. Our chitosan nanoparticles exhibited no cytotoxicity to RAW264 cells. Finally, we evaluated the immunostimulatory activity of CpG ODNs loaded on chitosan nanoparticles using human peripheral blood mononuclear cells. CpG ODNs significantly enhanced the secretion level of interleukin-6 and interferon-c by cells compared to the free CpG ODNs. These results indicated that chitosan nanoparticles could be a good candidate for the delivery of CpG ODNs.

Synthesis and characterization of chitosan nanoparticles of Achillea millefolium L. and their activities

“…Our DLS results are comparable to the average size of CSNPs reported in literature, i.e. 189 and 197 nm by Khan et al 32 , 216 nm by Agarwal et al 33 , and size range of 135-729 nm by Rasaee et al 34 and 6.5-1331.2 nm by Iswanti et al 35 . TEM of AMCSNPs in our study revealed a spherical shape with a smooth surface, which was also reported by Da Silva et al 21 .…”

Formulation, optimization and characterization of allantoin-loaded chitosan nanoparticles to alleviate ethanol-induced gastric ulcer: in-vitro and in-vivo studies

“…Consequently, in this survey, ALL-loaded chitosan/ sodium tripolyphosphate nanoparticles (ALL-loaded CS/STPP NPs) were prepared by ionotropic gelation technique and thoroughly characterized. A full 2 4 factorial design was adopted using four independently controlled parameters (ICPs). Comprehensive characterization, in vitro evaluations as well as antiulcerogenic activity study against ethanol-induced gastric ulcer in rats of the optimized NPs formula were conducted.…”

“…Such combination was asserted to be non-toxic and hindered the possibility of drug degradation. Moreover, CS-NPs are positively-charged with mucoadhesive as well as permeation enhancing properties, thus facilitate opening of the epithelial tight junctions [2][3][4] .…”

“…Optimization of ALL-loaded chitosan/sodium tripolyphosphate nanoparticles (ALL-loaded CS/STPP NPs) was performed by espousing 2 4 fully crossed design with four independently controlled parameters (ICPs) at two levels. The concentration of both CS (X 1 ) and STPP (X 2 ), CS:STPP volume ratio (X 3 ) and amount of ALL (X 4 ) were the different ICPs.…”

“…Amongst naturally occurring mucoadhesive cationic polysaccharides, chitosan (CS) has been extensively studied for PNPs preparation owing to its characteristic features. Low molecular weight (low MW) CS shows enhanced biocompatibility, biodegradability, solubility and less toxicity compared to high MW CS 3 , 4 . Ionotropic gelation method, an easy and attractive physical cross-linking process, is a cost-effective technique adopted to prepare chitosan nanoparticles (CS-NPs).…”