Influence of co-monomer ratio on the chemical properties and cytotoxicity of poly[acrylonitrile-co-(N-vinylpyrrolidone)] nanoparticles

Purpose. A system of nanoparticles with varying hydrophilicities may include promising biomaterial candidates as they offer various cellular uptake properties and a range of drug encapsulation efficacies, which would be advantageous in regenerative therapies. Therefore, a model system of nanoparticles with varying hydrophilicities was synthesized and assessed for its candidacy as a biomaterial. Methods. Here, acrylonitrile (AN) was copolymerized with N-vinylpyrrolidone (NVP) in a mini-emulsion to form a family of nanoparticles, thereby enabling the systematic variation of the copolymer hydrophilicity. The nanoparticles based on these copolymers were prepared and characterized using H-1-NMR, dynamic light scattering, differential scanning calorimetry, and thermal gravimetric analysis. Finally, the cytotoxicity of the nanoparticles was assessed by conducting indirect tests using L929 fibroblasts. Results. The nanoparticles showed well controlled NVP/AN molar ratios as determined by H-1 NMR, well defined diameters ranging from approximately 100 nm to 200 nm, and increasing glass transition temperatures with increasing molar NVP content. Finally, L929 fibroblasts only slightly changed their morphology upon incubation with material eluates. Conclusions. Poly[acrylonitrile-co-(N-vinylpyrrolidone)] nanoparticles with varying amounts of NVP were shown to be a promising model system for further biological assessment.