Plant Mediated Co-NPs & Fe-NPs by using Borage officinalis; Characterization and Biological Potential

Abstract

Green synthesis of metal nanoparticles using plant extracts is a promising route towards the synthesis of biologically active nanomaterials. Cobalt (Co) and iron (Fe) nanoparticles were produced in the current study using the Borago officinalis leaf extract which acted as a reducing and stabilizing agent. The UV-Visible spectroscopy revealed absorption peaks at about 520-540nm for Co-NPs and 280-320nm for Fe-NPs. Fourier-transform infrared spectroscopy (FTIR) was used to determine different functional groups like hydroxyl, carbonyl, and amine which can be attributed to phytochemicals of plants in the reduction and capping of the nanoparticles. The morphology of the nanoparticles in scanning electron microscopy (SEM) images revealed that they were almost spherical in shape with minimal agglomeration and average diameters ranging between 60-100nm. The obtained nanoparticle exhibited significant, concentration dependent antibacterial properties against Gram-positive and Gram-negative bacterial strains; cobalt nanoparticles formed larger zones of inhibition, an average of 18 mm, than iron nanoparticles, an average of 15 mm, but still lower than the conventional antibiotic. By the DPPH scavenging system, antioxidant activity reached maximum inhibition of about 78 and 67% in Co-NPs and Fe-NPs respectively at 1250 ug/mL, which equals IC50 of near 550 and 750 ug/mL respectively. All these findings highlight the potential of cobalt and iron nanoparticles based on Borago officinalis as safe antibacterial and antioxidant agents.