The influence of electron beam and gamma irradiation on paclitaxel-loaded nanoparticles of fully randomized copolymers in relation to potential sterilization

The presented report describes the evaluation of the influence of e-beam and γ-radiation on properties of the newly developed anticancer drug delivery systems (DDSs) based on biodegradable polymeric matrices: poly(ɛ-caprolactone) (PCL), poly(l-lactide) (PLA), poly(l-lactide-co-ɛ-caprolactone) (PLACL) and poly(ɛ-caprolactone-co-glycolide) (PCLGA), in relation to potential sterilization process. The physicochemical properties of the pharmaceutical formulations of paclitaxel (PTX)-loaded nanoparticles, as well as the basic polymeric matrices, were studied after irradiation with γ-rays and e-beam at sterilization dose 25 kGy. The structure of the polymers was found to be practically intact after the irradiation. Importantly, no PTX-related degradation products were detected after the irradiation. The results demonstrate, that the polyester based DDSs can realize sustained and controlled release of PTX. The kinetics of drug release were defined as first order with non-Fickian diffusion for all systems. The obtained results demonstrated a great potential of e-beam for the sterilization purposes of polymeric nanoparticles. In comparison, some effect on PTX release from the γ-irradiated copolymeric nanoparticles was observed due to faster polymer degradation. [Display omitted]