Abstract
This study reports the green biosynthesis of bioactive selenium nanoparticles using Catharanthus roseus extract as a reducing and stabilizing agent. Liquid chromatography-electrospray ionization tandem mass spectrometry profiling identified key phytoconstituents, including riboflavin 5'-phosphate and chlorogenic acid, involved in the process. Characterization confirmed successful synthesis: ultraviolet-visible spectroscopy showed an absorption peak at 266 nm, high-resolution transmission electron microscopy revealed spherical particles ranging from 8.6 to 65.6 nm, zeta potential was - 3.55 mV, and X-ray diffraction confirmed crystallinity. Fourier-transform infrared spectroscopy indicated the involvement of phenolic and carboxyl groups. The biosynthesized selenium nanoparticles exhibited broad-spectrum antimicrobial activity, antiviral action against adenovirus (half-maximal inhibitory concentration (IC(50)) = 22.99 µg/mL), and potent cytotoxicity against HepG2 hepatocellular carcinoma cells (IC(50)= 1.5 µg/mL). Molecular docking and dynamics simulations suggested stable interactions between seleniumphytochemical complexes and biological targets. Overall, this work demonstrates that C. roseus provides a sustainable route to novel, multifunctional selenium nanoparticles with promising preliminary bioactivity, establishing a foundation for future therapeutic development and in vivo studies.