Biogenic synthesis of nanostructured Gd2O3: Structural, optical and bioactive properties

Abstract

Nanostructured Gd2O3 has been synthesized using the leaf broth of Annona reticulate. The formation of nanoparticles is confirmed by XRD and TEM analysis. UV–visible and PL studies are employed to characterize the optical nature of the samples and the thermal analysis of the as prepared material has been performed to ascertain the proper annealing temperature. XRD pattern shows cubic structure with average particle size of about 25 nm. FTIR spectra reveal the possible biomolecules responsible for the formation of nanoparticles and their stabilization. Raman spectrum with characteristic band located at 360 cm−1 for the Fg mode supports the cubic phase of the nanostructured Gd2O3. Biocompatibility of synthesized nanoparticles is evaluated by carrying out the cytotoxic test against normal fibroblast cell lines and surviving fraction of normal cell lines are found to be above 75% up to a concentration of 50μg/mL. The antimicrobial activity of developed nanoparticles are screened against K. Pneumonae and S.aureus bacterial cell lines and substantial inhibition zones are observed in the dose dependent study. Moreover, this study also investigates the antioxidant efficacy of Gd2O3 nanoparticles using DPPH and superoxide free radical scavenging assays. With a concentration of 20μg/mL of the synthesized nanoparticles 70% scavenging is observed. The method of synthesis is simple, cost-effective and unexplored as it follows an ecofriendly protocol for the production of biologically active nanostructured Gd2O3.