Silver nanoparticles from leafy green extract of Belgian endive (Cichorium intybus L. var. sativus): Biosynthesis, characterization, and antibacterial activity

FERREYRA MAILLARD, A.P.V; PANNUNZIO MINER, E.V; GALLUCCI, M.N; PÁEZ, P.L; CORONADO, E.A; FRAIRE, J.C; AIASSA MARTÍNEZ, I.S; DALMASSO, P.R

MATERIALS LETTERS

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2017 vol. 197 p. 98 - 101

0167-577X

We report for the first time a green, simple, and low-cost synthesis of silver nanoparticles (AgNPs) bymixing AgNO3 solution with the aqueous leaf extract of Belgian endive, a variety of Cichorium intybusL., without any harmful reducing and capping agents. The biosynthesis of AgNPs was observed by thecolor charge from colorless (metal salt solution) to a yellowish brown (nanoparticle colloidal dispersion),which was confirmed by UV?vis spectroscopy, transmission electron microscopy (TEM), and X-raydiffraction (XRD). UV?vis spectra showed the surface plasmon resonance signature of AgNPs around420 nm, TEM revealed that nanoparticles were quasi-spherical with an average diameter ranging from19 to 64 nm depending on the metal salt concentration, and XRD pattern indicated that the biosyntheticprocess produced face-centered cubic AgNPs. Surface-enhanced Raman spectroscopy analysis showedthat the AgNPs were capped with bioactive molecules from the leaf extract, which are also believed tobe responsible for the bio-reduction of silver ions. The antibacterial activity of the biosynthesizedAgNPs was studied using both the disk diffusion and minimum inhibitory concentration methods againstStaphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa, and they were found to be effective atpicomolar concentration levels.