Triamcinolone acetonide-Eudragit(®) RS100 nanofibers and nanobeads: Morphological and physicochemical...

The aim of the present research was to fabricate triamcinolone acetonide (TA)-Eudragit(®) RS100 nanostructures using the electrospraying method.

The physicochemical properties of the electrosprayed formulations as well as drug release patterns were assessed. The particle size and morphology were evaluated using scanning electron microscopy. X-ray crystallography and differential scanning calorimetry were also conducted to investigate the crystallinity and polymorphic alterations of the drug in the formulations. Probable chemical interactions between the drug and the carrier during the preparation process were analyzed using FT-IR spectroscopy. The drug release kinetic was also considered to predict the release mechanism.

Increasing the concentration of injected polymer solution resulted in the formation of more fibers and fewer beads, with the particle diameter ranging from 60 nm to a few micrometers based on the drug: polymer ratio. The drug crystallinity was notably decreased during the electrospraying process; however, no interaction between drug and polymer was detected. The electrosprayed formulations with 1:10 drug: polymer ratio showed an almost similar drug release rate compared to the pure drug, while those with 1:5 ratio revealed slower release profiles. The release data were best fitted to the Weibull model, so that the corresponding shape factor values of the Weibull model were less than 0.75, indicating the diffusion controlled release mechanism.

Our findings revealed that TA loaded Eudragit(®) RS100 nanofibers and nanobeads were properly prepared by the electrospraying method, which is a simple, surfactant-free and cost effective technique for producing drug: polymer nanostructures.