Indomethacin-loaded poly(butylcyanoacrylate) nanoparticles: preparation and characterization

This paper describes a method to prepare indomethacin-loaded poly(butylcyanoacrylate) (PBCA) nanoparticles based on the anionic polymerization procedure, often used in the synthesis of poly(alkylcyanoacrylate) (PACA) nanoparticles for drug delivery. A detailed investigation into the capability of the polymeric nanoparticles to load this drug is discussed, along with the effect of the technique parameters on characteristics of the nanoparticles. The results indicated that indomethacin-loaded PBCA nanoparticles showed a particle size distribution that could be successfully exploited for the formulation of colloidal pharmaceutical systems. The particles were predominantly less than 200 nm in size with a negative charge, and rather stable when pH was adjusted to neutral. In addition, X-ray diffraction experiments revealed that the drug would be molecularly dispersed in the polymers in an amorphous state and crystalline with very small size. In vitro drug release revealed that indomethacin incorporation and/or adsorption led to a rapid drug release followed by a slower release in biological phosphate buffer and that the release rate decreased with increasing indomethacin content in the particle.