International Conference on Applications of Radiation Science and Technology

Nanogels of Polyvinylpyrrolidone Obtained by Gamma Radiation. Physicochemical and Biological Characterization

27 Apr 2017, 14:15

2h

IAEA Board Room B/M1 (IAEA Headquarters)

Poster RADIATION SYNTHESIS AND MODIFICATION OF MATERIALS P-A2

Speaker

Mr Manuel Rapado Paneque (Center for Applied Technologies and Nuclear Development CEADEN, Cuba)

Description

Background of the study Nanogels are nanoscale polymeric matrices with strong affinity for aqueous media. They exhibit stability, are inert to blood flow and favour the incorporation of medicinal drugs and bioactive molecules improving their therapeutic value by increasing bioavailability, solubility and retention time. The aim of this work was the preparation of polyvinylpyrrolidone nanogels induced by $\gamma$-irradiation, for evaluation as potential drug delivery system. Methodology Experiments were performed in absence of oxygen using diluted aqueous solutions of PVP. The synthesis was carried out in sealed vials in N$_2$O atmosphere irradiated with different absorbed doses on a $\gamma$-irradiation facility ISOGAMMA LLCo. The nanogels were characterized by viscometry, spectroscopy (ATR and UV-vis), thermogravimetry (TGA), diffraction (XRD), electron microscopy (TEM and SEM), dynamic light scattering. Cytotoxicity studies were performed by the of NBT and MTT tests. Results The viscometric results show a decrease in intrinsic viscosity with increasing dose accompanied by an increase in molecular weight. Such behaviour indicates the formation of intramolecular cross-linking by nanogels. The nanogels have an average size of $50$ nm with a dispersion of $1.04$. The XRD showed certain order in the morphology of the nanogels. Gels are spherical in shape and have a marked protective effect on cell viability. In the interval of concentrations studied ($0.001$–$0.8\%$) the more dilute systems favoured the formation of nanogels, whereas the more concentrated ones promoted the appearance of microgels IR spectra and thermal behaviour of nanogels coincided with those of the polymer in bulk. Biological test showed a high biocompatibility. Conclusion Nano PVP gels were obtained using $\gamma$-radiation. It was shown that the degree of cross-linking of the polymer depends on nanogels concentration and the absorbed dose. The obtained nanogels do not exhibit toxicity to cells, and rather have a protective or stimulator effect on cell viability, property which makes them good candidates as platforms for delivery systems.