Biogeneration of silver nanoparticles from Cuphea procumbens for biomedical and environmental applications

Abstract

AbstractNanotechnology is one of the most important and relevant disciplines today due to the specific electrical, optical, magnetic, chemical, mechanical and biomedical properties of nanoparticles. In the present study we demonstrate the efficacy ofCuphea procumbensto biogenerate silver nanoparticles (AgNPs) with antibacterial and antitumor activity. These nanoparticles were synthesized using the aqueous extract ofC. procumbensas reducing agent and silver nitrate as oxidizing agent. The Transmission Electron Microscopy demonstrated that the biogenic AgNPs were predominantly quasi-spherical with an average particle size of 23.45 nm. The surface plasmonic resonance was analyzed by ultraviolet visible spectroscopy (UV–Vis) observing a maximum absorption band at 441 nm and Infrared Spectroscopy (FT IR) was used in order to structurally identify the functional groups of some compounds involved in the formation of nanoparticles. The AgNPs demonstrated to have antibacterial activity against the pathogenic bacteriaEscherichia coliandStaphylococcus aureus, identifying the maximum zone of inhibition at the concentration of 0.225 and 0.158 µg/mL respectively. Moreover, compared to the extract, AgNPs exhibited better antitumor activity and higher therapeutic index (TI) against several tumor cell lines such as human breast carcinoma MCF-7 (IC50of 2.56 µg/mL, TI of 27.65 µg/mL), MDA-MB-468 (IC50of 2.25 µg/mL, TI of 31.53 µg/mL), human colon carcinoma HCT-116 (IC50of 1.38 µg/mL, TI of 51.07 µg/mL) and melanoma A-375 (IC50of 6.51 µg/mL, TI of 10.89 µg/mL). This fact is of great since it will reduce the side effects derived from the treatment. In addition, AgNPs revealed to have a photocatalytic activity of the dyes congo red (10–3 M) in 5 min and malachite green (10–3 M) in 7 min. Additionally, the degradation percentages were obtained, which were 86.61% for congo red and 82.11% for malachite green. Overall, our results demonstrated for the first time thatC. procumbensbiogenerated nanoparticles are excellent candidates for several biomedical and environmental applications.