Self-assembled high molecular weight inulin nanoparticles: Enzymatic synthesis, physicochemical and biological properties.

•HMW inulin enzymatically-synthesized is self-assembled into nanoparticles.•The assemblage of inulin nanoparticles is carried out during enzymatic synthesis.•The inulin forms nanoparticles at a critical aggregation concentration (CAC).•The CAC and nanoparticle size are influenced by the reaction temperature.•The inulin nanoparticles are not toxic for peripheral blood mononuclear cells.