Abstract
Human malignancies are one of the potent targeted diseases for therapeutics based on RNA. There are many barriers for effective delivery of siRNA to cell, since it is rapidly degraded by RNAse and macrophages. Polymeric nanoparticles are used extensively for the transport of genes across cell membranes. Among all polycationic polymers chitosan (CS) has been widely used. Cross-linkers are very important in the production of stable nanoparticles. The most commonly used cross-linkers in the preparation of CS nanoparticles are sodium tripolyphosphate (TPP) and dextran sulfate (DS). In current study, the researchers aim to formulate siRNA-loaded CS-TPP and CS-DS nanoparticles by adsorption method and to compare these nanoparticles on the basis of physicochemical characterizations. By changing the CS concentration from 0.1 to 0.4% w/v, the siRNA loaded CS-TPP and CS-DS nanoparticles were successfully prepared with average diameter of +24.8 +/- 1.5 to +43.2 +/- 0.5 and +44.7 +/- 4.0 to +63.0 +/- 1.2, respectively. siRNA-loaded CS-TPP nanoparticles showed spherical morphology while CS-DS nanoparticles showed irregular morphology. All nanoparticles showed high encapsulation efficiency. The release profile for nanoparticles prepared by both cross-linkers were also observed. Based on the results, siRNA-loaded CS-TPP nanoparticles show a great potential for clinical use in siRNA-based cancer therapies.