Piroxicam Nanoparticles for Ocular Delivery: Physicochemical Characterization and Implementation in Endotoxin-induced Uveitis

To investigate the anti-inflammatory impacts of piroxicam nanosuspension, in the current investigation, piroxicam:Eudragit wRS100 nanoformulations were used to control inflammatory symptoms in the rabbits with endotoxin-induced uveitis (EIU). The nanoparticles of piroxicam:EudragitwRS100 was formulated using the solvent evaporation/extraction technique. The morphological and physicochemical characteristics of nanoparticles were studied using particle size analysis, X-ray crystallography, differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Drug release profileswere examined by fitting the data to the most common kineticmodels. Selected nanosuspensionswere used to assess the anti-inflammatory impacts of piroxicamnanoparticles in the rabbitswithEIU.Themajor

symptoms of EIU(i.e. inflammation and leukocytes numbers in the aqueous humor) were examined. All the prepared piroxicam formulations using EudragitwRS100 resulted in a nano-range size particles and displayed spherical smooth morphology with positively charged surface, however, the formulated particles of drug alone using same methodology failed to manifest such characteristics. The EudragitwRS100 containing nanoparticles displayed lower crystallinity than piroxicam with no chemical

interactions between the drug and polymermolecules. Kinetically, the release profiles of piroxicam from nanoparticles appeared to fit best with the Weibull model and diffusion was the superior phenomenon. The in vivo examinations revealed that the inflammation can be inhibited by the drug:polymer nanosuspension more significantly than themicrosuspension of drug alone in

the rabbitswith EIU.Upon these findings,we propose that the piroxicam:EudragitwRS100 nanosuspensionsmay be considered as an improved ocular delivery system for locally inhibition of inflammation.