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

Abstract

Nanotechnology 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 of Cuphea procumbens to biogenerate silver nanoparticles (AgNPs) with antibacterial and antitumor activity. These nanoparticles were synthesized using the aqueous extract of C. procumbens as 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 bacteria Escherichia coli and Staphylococcus 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 (IC50 of 2.56 µg/mL, TI of 27.65 µg/mL), MDA-MB-468 (IC50 of 2.25 µg/mL, TI of 31.53 µg/mL), human colon carcinoma HCT-116 (IC50 of 1.38 µg/mL, TI of 51.07 µg/mL) and melanoma A-375 (IC50 of 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 that C. procumbens biogenerated nanoparticles are excellent candidates for several biomedical and environmental applications.

Effect of Biosynthesized Silver Nanoparticles on The Optical, Structural, and Morphological Properties of TiO2 Nanocrystals

“…On close inspection of the spectrum, the AgNPs shows a broad band with a visible peak observed at 465 nm which correspond to the plasmonic absorption of AgNPs [3,[17][18][19][20]. The surface plasmon resonance effect is due to the mutual oscillation of conduction electrons which are in resonance with the light wave.…”

Green Synthesis of Highly Monodisperse and Spherical Ag Nanoparticles by a Combination of Teucrium ramosissimum Desf. (Lamiaceae) Extracts with Emphasis on the Stabilizing and Capping Biomolecules

“…The reaction time also plays an important role in the green synthesis of Ag NPs, ,,,, and after optimizing the pH value and the amount of extract to obtain the best Ag NPs, the synthesis was performed at two different reaction times, 4 and 6 h, again based on our previous reported protocol . Indeed, after these periods of synthesis, we have investigated the possibility of performing on the just generated Ag NPs an incubation period of 12 h at room temperature.…”

“…For this reason, in recent years, the synthesis of Ag NPs has been carried out using safer, healthier, and more environmentally friendly methods arising from vegetal origin. ,, These procedures are encompassed within the designated green chemistry strategies and are a consequence of the fact that the bioactive compounds contained in these vegetal extracts serve the dual functions of both reducing and capping agents. In this sense, plant, lichen, or fruit extracts, as well as enzymes or bacteria, are currently used in green chemistry procedures to obtain Ag NPs. ,,− These extracts include a multitude of natural compounds, such as polysaccharides, antioxidants, flavonoids, terpenoids, phenolic compounds, and organic acids, ,, which makes plant extracts highly bioactive and amenable to green chemistry synthesis. ,, As an example, Ag NPs have been synthesized using tea leaf, coffee extracts, grape pomace, beet juice, and also with extracts derived from pepper, blueberry, geranium, aloe vera, and hibiscus, among others. − Table S1 includes previously reported protocols for the green synthesis of Ag NPs performed as a function of several parameters, such as pH, − temperature, , reaction time, , or incubation time. , This table includes the type of extract used for the synthesis of Ag NPs, the parameters investigated in each case, the particle size, and the reference. Indeed, this table provides empirical evidence demonstrating that the utilization of these vegetal extracts leads to the formation of polydisperse particle distributions, wherein deviations from the average diameter typically fall within the range of several to tens of nanometers.…”

Therapeutic Applications of Biogenic Silver Nanomaterial Synthesized from the Paper Flower of Bougainvillea glabra (Miami, Pink)

“…Additional Bragg peaks were also detected at 27.65°, 29.65°, 32.25°, 35.5°, 38.4°, 46.25°, 53.8°, and 81.05°, which were involved in silver nanocrystal formation. These additional peaks occurred due to organic compounds from the plants that stabilize and reduce silver ions into elemental nanoparticles [ 45 ].…”