Development and assessment of silver-zinc dual doped silymarin nanocrystals for multifunctional photocatalytic, antibacterial, and cytotoxic applications

This research aims to develop aqueous-soluble Ag/Zn-doped silymarin nanocrystals (SNCs) from Silybum marianum extract using the solvent evaporation technique as an innovative platform to enhance the bioactivity of silymarin. The synthesized nanocrystals were evaluated for their antibacterial, cytotoxic, and photocatalytic activities, highlighting their potential as multifunctional silymarin-based nanomaterials. XRD analysis of the Ag/Zn dual-doped SNCs indicated amorphous structures. TEM and FESEM images revealed that the Ag/Zn dual-doped SNCs exhibited spherical characteristics, with a mean size of about 33.83 nm. FTIR spectroscopy confirmed the characteristic functional groups of silymarin and indicated the successful incorporation of Ag and Zn into the nanocrystal structure. The results of the UV-Vis analysis demonstrated that the Ag/Zn dual-doped SNCs exhibited strong absorption peaks at 233, 289, and 449 nm. The EDX and mapping analyses confirmed the elemental composition and the successful incorporation of Ag and Zn into the silymarin nanocrystals. The results from the photocatalytic test showed that Ag/Zn dual-doped SNCs achieved a 98% degradation of the MB (methylene blue) dye. The MTT results demonstrated that Ag/Zn dual-doped SNCs had moderate toxicity toward cancer MDA-MB-231 cells (IC 50 value of 389.7 µg/mL). Furthermore, the antibacterial outcomes indicated that the Ag/Zn dual-doped SNCs displayed enhanced effectiveness against Pseudomonas aeruginosa and Staphylococcus aureus (ATCC strains) compared to clinical strains.