Phytogenic synthesis of gold-ruthenium (Au-Ru) bimetallic nanoparticles using Aloe vera gel and evaluation of their anticancer potential.

Bimetallic nanoparticles are a key focus in contemporary cancer research because of their efficacy and advantages over conventional monometallic nanoparticles. However, there are very few suitable methods available for their synthesis. Therefore, in the present study, gold-ruthenium (Au-Ru) bimetallic nanoparticles were synthesized using a green, successive-growth approach, with Aloe vera gel acting as a natural reducing and stabilizing agent. The synthesized nanoparticles were characterized using UV-visible spectrophotometry, Fourier Transform Infrared Spectroscopy (FT-IR), High Resolution Transmission Electron Microscopy (HRTEM), Powder X-ray Diffraction (PXRD), Field Emission Scanning Electron Microscopy (FESEM) and Energy Dispersive X-ray spectroscopy (EDX). HRTEM images of Au-Ru NPs at different scales confirm the formation of hexagonal bimetallic Au-Ru NPs of size in the range 19.04-76.19 nm while EDX showed reveals the presence of both the metal. Comparative anticancer evaluation of Au and Au-Ru nanoparticles was carried out in Dalton's lymphoma ascites (DL) cells using the Trypan Blue assay. The IC50 value of Au-Ru NPs was 18.34 ± 0.02 µM showing highest potency, while IC50 value of AuNPs was 46.7 ± 0.018 µM indicating significantly enhanced anticancer activity. Additionally, bothnanoparticles showed minimal impact (<10%) on non-cancerous PBMC cell lines suggesting it is the least harmful to healthy tissues among the treatments.