Factorial design as tool in chitosan nanoparticles development by ionic gelation technique

Since there are different kinds of chitosan, obtained from different sources of chitin and routes, it is very important to study which are the best conditions in order to obtain nanoparticles with desired size and superficial charge. The aim of this paper was to demonstrate to the scientific community how to obtain chitosan nanoparticles (nanoCTS) with these properties. Ionic gelation technique was applied to form nanoparticles through linkages between tripolyphosphate (TPP) and chitosan (CTS). The formulation was optimized using a 23 factorial design to analyze the effect of the pH, CTS:TPP ratio and acetic acid concentration in size and charge of the particles. The best formulation was characterized by FTIR, TGA, EDX and TEM analysis. The formation of nanoCTS depended mainly on ratio of CTS:TPP. Nanoparticles were obtained with excellent conditions for the application in pharmaceutical studies: average diameter of 76.2 nm and zeta potential of 32.6 mV.