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Stability, Intracellular Delivery, and Release of siRNA from Chitosan Nanoparticles Using Different Cross-Linkers.

Raja MA, Katas H, Jing Wen T - PLoS ONE (2015)

Bottom Line: The resulting nanoparticles were compared with regard to their physicochemical properties including particle size, zeta potential, morphology, binding and encapsulation efficiencies.The cellular uptake studies with CS-TPP-siRNA nanoparticles showed successful delivery of siRNA within cytoplasm of DLD-1 cells.The results demonstrate that ionically cross-linked CS-TPP nanoparticles are biocompatible non-viral gene delivery system and generate a solid ground for further optimization studies, for example with regard to steric stabilization and targeting.

View Article: PubMed Central - PubMed

Affiliation: Centre for Drug Delivery Research, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.

ABSTRACT
Chitosan (CS) nanoparticles have been extensively studied for siRNA delivery; however, their stability and efficacy are highly dependent on the types of cross-linker used. To address this issue, three common cross-linkers; tripolyphosphate (TPP), dextran sulphate (DS) and poly-D-glutamic acid (PGA) were used to prepare siRNA loaded CS-TPP/DS/PGA nanoparticles by ionic gelation method. The resulting nanoparticles were compared with regard to their physicochemical properties including particle size, zeta potential, morphology, binding and encapsulation efficiencies. Among all the formulations prepared with different cross linkers, CS-TPP-siRNA had the smallest particle size (ranged from 127 ± 9.7 to 455 ± 12.9 nm) with zeta potential ranged from +25.1 ± 1.5 to +39.4 ± 0.5 mV, and high entrapment (>95%) and binding efficiencies. Similarly, CS-TPP nanoparticles showed better siRNA protection during storage at 4˚C and as determined by serum protection assay. TEM micrographs revealed the assorted morphology of CS-TPP-siRNA nanoparticles in contrast to irregular morphology displayed by CS-DS-siRNA and CS-PGA-siRNA nanoparticles. All siRNA loaded CS-TPP/DS/PGA nanoparticles showed initial burst release followed by sustained release of siRNA. Moreover, all the formulations showed low and concentration-dependent cytotoxicity with human colorectal cancer cells (DLD-1), in vitro. The cellular uptake studies with CS-TPP-siRNA nanoparticles showed successful delivery of siRNA within cytoplasm of DLD-1 cells. The results demonstrate that ionically cross-linked CS-TPP nanoparticles are biocompatible non-viral gene delivery system and generate a solid ground for further optimization studies, for example with regard to steric stabilization and targeting.

No MeSH data available.


Related in: MedlinePlus

Entrapment efficiency of siRNA-loaded CS-TPP/DS/PGA nanoparticles prepared using different CS concentrations (0.1% to 0.4% w/v CS), n = 3.
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pone.0128963.g002: Entrapment efficiency of siRNA-loaded CS-TPP/DS/PGA nanoparticles prepared using different CS concentrations (0.1% to 0.4% w/v CS), n = 3.

Mentions: An siRNA entrapment efficiency in the range of 85% to 99% was achieved for CS-TPP/DS/PGA nanoparticles. In general, the entrapment efficiencies of all formulations decreased when CS concentration was increased, as shown in Fig 2. The entrapment efficiency of siRNA-loaded CS-TPP, CS-DS, and CS-PGA formulations was decreased significantly by increasing CS concentration from 0.1% to 0.4% w/v. Higher CS concentrations produced a more viscous solution that hindered the movement of siRNA around the CS chain and led to inefficient siRNA entrapment[31]. The low entrapment efficiency of CS-DS-siRNA and CS-PGA-siRNA may be explained by shielding effects and steric hindrance, which interfered with the interaction between siRNA and CS NH3+ groups[32].


Stability, Intracellular Delivery, and Release of siRNA from Chitosan Nanoparticles Using Different Cross-Linkers.

Raja MA, Katas H, Jing Wen T - PLoS ONE (2015)

Entrapment efficiency of siRNA-loaded CS-TPP/DS/PGA nanoparticles prepared using different CS concentrations (0.1% to 0.4% w/v CS), n = 3.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4465927&req=5

pone.0128963.g002: Entrapment efficiency of siRNA-loaded CS-TPP/DS/PGA nanoparticles prepared using different CS concentrations (0.1% to 0.4% w/v CS), n = 3.
Mentions: An siRNA entrapment efficiency in the range of 85% to 99% was achieved for CS-TPP/DS/PGA nanoparticles. In general, the entrapment efficiencies of all formulations decreased when CS concentration was increased, as shown in Fig 2. The entrapment efficiency of siRNA-loaded CS-TPP, CS-DS, and CS-PGA formulations was decreased significantly by increasing CS concentration from 0.1% to 0.4% w/v. Higher CS concentrations produced a more viscous solution that hindered the movement of siRNA around the CS chain and led to inefficient siRNA entrapment[31]. The low entrapment efficiency of CS-DS-siRNA and CS-PGA-siRNA may be explained by shielding effects and steric hindrance, which interfered with the interaction between siRNA and CS NH3+ groups[32].

Bottom Line: The resulting nanoparticles were compared with regard to their physicochemical properties including particle size, zeta potential, morphology, binding and encapsulation efficiencies.The cellular uptake studies with CS-TPP-siRNA nanoparticles showed successful delivery of siRNA within cytoplasm of DLD-1 cells.The results demonstrate that ionically cross-linked CS-TPP nanoparticles are biocompatible non-viral gene delivery system and generate a solid ground for further optimization studies, for example with regard to steric stabilization and targeting.

View Article: PubMed Central - PubMed

Affiliation: Centre for Drug Delivery Research, Faculty of Pharmacy, Universiti Kebangsaan Malaysia, Jalan Raja Muda Abdul Aziz, Kuala Lumpur, Malaysia.

ABSTRACT
Chitosan (CS) nanoparticles have been extensively studied for siRNA delivery; however, their stability and efficacy are highly dependent on the types of cross-linker used. To address this issue, three common cross-linkers; tripolyphosphate (TPP), dextran sulphate (DS) and poly-D-glutamic acid (PGA) were used to prepare siRNA loaded CS-TPP/DS/PGA nanoparticles by ionic gelation method. The resulting nanoparticles were compared with regard to their physicochemical properties including particle size, zeta potential, morphology, binding and encapsulation efficiencies. Among all the formulations prepared with different cross linkers, CS-TPP-siRNA had the smallest particle size (ranged from 127 ± 9.7 to 455 ± 12.9 nm) with zeta potential ranged from +25.1 ± 1.5 to +39.4 ± 0.5 mV, and high entrapment (>95%) and binding efficiencies. Similarly, CS-TPP nanoparticles showed better siRNA protection during storage at 4˚C and as determined by serum protection assay. TEM micrographs revealed the assorted morphology of CS-TPP-siRNA nanoparticles in contrast to irregular morphology displayed by CS-DS-siRNA and CS-PGA-siRNA nanoparticles. All siRNA loaded CS-TPP/DS/PGA nanoparticles showed initial burst release followed by sustained release of siRNA. Moreover, all the formulations showed low and concentration-dependent cytotoxicity with human colorectal cancer cells (DLD-1), in vitro. The cellular uptake studies with CS-TPP-siRNA nanoparticles showed successful delivery of siRNA within cytoplasm of DLD-1 cells. The results demonstrate that ionically cross-linked CS-TPP nanoparticles are biocompatible non-viral gene delivery system and generate a solid ground for further optimization studies, for example with regard to steric stabilization and targeting.

No MeSH data available.


Related in: MedlinePlus