Formulation, characterization and in vitro release study of 5-fluorouracil loaded chitosan nanoparticles

The main objective of this study was to evaluate the most suitable conditions to prepare 5-fluorouracil (5-FU) loaded chitosan nanoparticles (CSNPs). 5-FU loaded CSNPs were prepared employing the ionic gelation technique using three different molecular weights of CS with the polyanion sodium tripolyphosphate (STPP) as cross-linking agent. The preparation was based on the ionic interaction of positively charged CS and negatively charged STPP. The entrapment efficiency (EE%) of CSNPs was in the range of 3.86-21.82% EE% exhibited a clear increase with increasing CS concentration. The averge particles size was in the nanosize range and monodisperse in nature whereas transmission electron microscope micrographs showed that the prepared nanoparticles have a spherical shape. Fourier transform infrared (FTIR), X- ray differaction (XRD) and differential scanning calorimetry (DSC) confirmed successful incorporation of 5-FU in prepared CSNPs. In vitro release of 5-FU from selected formulations exhibited sustained release from the nanoparticles where slower release was observed when higher molecular weight CS was used. The study of drug release kinetics revealed that the release of 5-FU from CSNPs followed a diffusion controlled pattern.