Preparation of Diclofenac Acid Loaded- PCL Nanoparticles by Nanoprecipitation Method

Diclofenac acid loaded-nanoparticles in either polycaprolactone of Mn 10,000 or of  Mn 45,000 were prepared by nanoprecipitation method. Nearly 60% of Diclofecac acid has been released during 66 hours via a diffusion mechanism following the Korsmeyer-Peppas model, which showed the best fit and highest correlation coefficient among the five release models studied. According to 'n' exponent of the Korsmeyr-peppas model, diffusion has been proved to be the dominant mechanism during the release of diclofenac acid. The nanoparticles were spherical and very homogeneous in their sizes according to the fact that the value of polydispersity index was less than 0.5 with a value equal to '0.035±0.072'. The hydrodynamic nanoparticle radius has been '87.47±2.724' nanometer. Additionally, more than 75% of diclofenac acid has been successfully encapsulated into nanoparticles. These properties indicate the suitability of this nanotechnology system for drug delivery and release, with the potential use of polymeric nanoparticles as a promising system for controlled drug release.  Nanoparticles of polycaprolactone 10,000 were also prepared by the same preparation method in order to compare the effect of the polymer's molecular weight on the physicochemical properties of the prepared particles. The nanoparticles prepared with the lower molecular weight polymer exhibited smaller sizes compared to those prepared with the higher molecular weight polymer, with an average hydrodynamic diameter of 62.9 ± 0.57 nm. There was no statistically significant difference in the polydispersity index between the two formulations; however, the zeta potential was clearly lower, not exceeding 4.2 ± 17 mV.