Synthesis of anthraquinone-capped TiO2 nanoparticles using R-emodi roots: preparation, characterization and cytotoxic potential

Rheum emodi is a Himalayan herb of family Polygonaceace, known for its medicinal properties owing to the presence of chrysophanol, emodin, physcion, aloe emodi anthraquinones as major constituents. The present investigation aims to synthesize TiO2 nanoparticles (TiO2 NPs) using R. emodi root extract. The synthesized nanoparticles were characterized using UV-Vis, FTIR, FESEM, EDX, AFM, TEM and XRD techniques. UV-visible spectra indicated the surface plasmon resonance (SPR) at 336 nm. The size distribution profiles were analyzed through XRD which revealed the crystalline nature of nanoparticles with average size of 45 nm. TEM and SEM micrographs showed that the particles are spherical and uneven. FTIR spectra reflected the evidence of the presence of anthraquinones, possible bio-molecules responsible for stabilization, reduction and capping of TiO2 NPs. The cytotoxic potential of TiO2 NPs was tested against liver cancer cells (HepG2) lines which was found very effective and the formulation can be used in nano-drug to treat cancer cells in future.