TY - JOUR

T1 - Hypericum perforatum L.-mediated green synthesis of silver nanoparticles exhibiting antioxidant and anticancer activities

AU - Alahmad, Abdalrahim

AU - Feldhoff, Armin

AU - Bigall, Nadja C.

AU - Rusch, Pascal

AU - Scheper, Thomas

AU - Walter, Johanna Gabriela

N1 - Funding Information: A.A. thanks the Avicenna-Studienwerk for financial support. Acknowledgments: The authors are grateful to all the lab members for their help. The authors express their gratitude to Frank Steinbach (Department of Physical Chemistry PCI, Leibniz Universit?t Hannover) for support with SEM; XRD and TEM analysis. From the same Department we thank also rer. nat. Dirk Dorfs. We thank rer. nat. Claus R?scher from mineralogy department Leibniz Universit?t Hannover for providing ATR, FTIR and Raman analysis. I would like to express my great appreciation to Antonina Lavrentieva (Institute for Technical Chemistry TCI, Leibniz Univer-sit?t Hannover) for her advice and assistance during the study of cytotoxicity of AgNPs. Abdalrahim Alahmad is supported by doctoral grants from Avicenna Studienwerk e.V. We are very thankful to Ibrahim Alghoraibi, leader of the Nanotechnology activity of the Physics Department, Damascus for his valuable suggestions during this work. N.C.B. thanks the European Research Council (European Union?s Horizon 2020 research, innovation program, grant agreement 714429), and the DFG (grant agreement BI 1708/4-1) for financial support. N.C.B. thanks also the Laboratory for Nano and Quantum Engineering (LNQE). The publication of this article was funded by the Open Access Publishing Fund of Leibniz Universit?t Hannover.

PY - 2021/2/14

Y1 - 2021/2/14

N2 - This contribution focuses on the green synthesis of silver nanoparticles (AgNPs) with a size < 100 nm for potential medical applications by using silver nitrate solution and Hypericum Per-foratum L. (St John’s wort) aqueous extracts. Various synthesis methods were used and compared with regard to their yield and quality of obtained AgNPs. Monodisperse spherical nanoparticles were generated with a size of approximately 20 to 50 nm as elucidated by different techniques (SEM, TEM). XRD measurements showed that metallic silver was formed and the particles possess a face-centered cubic structure (fcc). SEM images and FTIR spectra revealed that the AgNPs are covered by a protective surface layer composed of organic components originating from the plant extract. Ultraviolet-visible spectroscopy, dynamic light scattering, and zeta potential were also measured for biologically synthesized AgNPs. A potential mechanism of reducing silver ions to silver metal and protecting it in the nanoscale form has been proposed based on the obtained results. Moreover, the AgNPs prepared in the present study have been shown to exhibit a high antioxidant activity for 2, 2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation, and super oxide anion radical and 2,2-diphenyl-1-picrylhydrazyl. Synthesized AgNPs showed high cytotoxicity by inhibiting cell viability for Hela, Hep G2, and A549 cells.

AB - This contribution focuses on the green synthesis of silver nanoparticles (AgNPs) with a size < 100 nm for potential medical applications by using silver nitrate solution and Hypericum Per-foratum L. (St John’s wort) aqueous extracts. Various synthesis methods were used and compared with regard to their yield and quality of obtained AgNPs. Monodisperse spherical nanoparticles were generated with a size of approximately 20 to 50 nm as elucidated by different techniques (SEM, TEM). XRD measurements showed that metallic silver was formed and the particles possess a face-centered cubic structure (fcc). SEM images and FTIR spectra revealed that the AgNPs are covered by a protective surface layer composed of organic components originating from the plant extract. Ultraviolet-visible spectroscopy, dynamic light scattering, and zeta potential were also measured for biologically synthesized AgNPs. A potential mechanism of reducing silver ions to silver metal and protecting it in the nanoscale form has been proposed based on the obtained results. Moreover, the AgNPs prepared in the present study have been shown to exhibit a high antioxidant activity for 2, 2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) radical cation, and super oxide anion radical and 2,2-diphenyl-1-picrylhydrazyl. Synthesized AgNPs showed high cytotoxicity by inhibiting cell viability for Hela, Hep G2, and A549 cells.

KW - ABTS

KW - Antioxidant and cytotoxicity effects

KW - DPPH

KW - Hypericum perforatum L. (St John’s wort)

KW - Mechanism of green formation of nanoparticles

KW - Silver nanoparticles (AgNPs)

KW - Hypericum perforatum L. (St John's wort)

KW - silver nanoparticles (AgNPs)

KW - mechanism of green formation of nanoparticles

KW - antioxidant and cytotoxicity effects

UR - http://www.scopus.com/inward/record.url?scp=85100737346&partnerID=8YFLogxK

U2 - 10.3390/nano11020487

DO - 10.3390/nano11020487

M3 - Article

AN - SCOPUS:85100737346

VL - 11

SP - 1

EP - 26

JO - Nanomaterials

JF - Nanomaterials

SN - 2079-4991

IS - 2

M1 - 487

ER -