COMBINED POLY(ISOBUTYLCYANOACRYLATE) AND CYCLODEXTRINS NANOPARTICLES FOR ENHANCING THE ENCAPSULATION OF LIPOPHILIC DRUGS

Purpose. The aim of this study was to prepare and characterize nano-pa rticulate systems constituted of poly(isobutylcyanoacrylate) and cyclo dextrins and intended for increasing the loading of the particles with lipophilic substances. Progesterone was used as a model substance. Me thods. Nanoparticles were prepared by polymerization of isobutylcyanoa crylate in presence of cyclodextrins or progesterone/hydroxypropyl-bet a-cyclodextrin complex. Particle size, zeta potential, cyclodextrin an d progesterone loading of the particles were determined. Results. Nano particles could be easily prepared in presence of cyclodextrins. An in crease in hydroxypropyl-beta-cyclodextrin concentration resulted in sm all nanoparticles (less than 50 nm). It was found that large amounts o f cyclodextrins remained associated to the particles, resulting in a 5 0 fold increase in progesterone loading compared to nanoparticles prep ared in absence of cyclodextrins. Conclusions. The poly(isobutylcyanoa crylate)-cyclodextrin nanoparticles were characterized by the presence of many lipophilic sites belonging to the cyclodextrins which were fi rmly anchored to the structure of the particles. Therefore, this new t ype of nanoparticles offers probably an opportunity for increasing the loading of nanoparticles with various lipophilic drugs.