Templated green synthesis of plasmonic silver nanoparticles in onion epidermal cells suitable for surface-enhanced Raman and hyper-Raman scattering

• Marta Espina Palanco,
• Klaus Bo Mogensen,
• Marina Gühlke,
• Zsuzsanna Heiner,
• Janina Kneipp and
• Katrin Kneipp

Beilstein J. Nanotechnol. 2016, 7, 834–840, doi:10.3762/bjnano.7.75

• demonstrate a templated green preparation of enhancing plasmonic nanoparticles and suggest a new route to deliver silver nanoparticles as basic building blocks of plasmonic nanosensors to plants by the uptake of solutions of metal salts. Keywords: biotemplates; green preparation; onion; plasmonic

• stabilizing agents. This gives rise to a broad variety of parameters in the green preparation process, resulting in metal nanoparticles of different sizes and shapes. While pre-treated plant materials such as extract and juice have been used in former studies [14][15][18][19][20]. In this article, we

• demonstrate and discuss the green preparation of plasmonic silver nanoparticles in intact onion epidermal cells after incubation with AgNO3 solution. The onions deliver reducing and stabilizing chemicals, while the histological structure of the onion layer, in particular the cell walls and the extracellular

Green preparation and spectroscopic characterization of plasmonic silver nanoparticles using fruits as reducing agents

• Jes Ærøe Hyllested,
• Marta Espina Palanco,
• Nicolai Hagen,
• Klaus Bo Mogensen and
• Katrin Kneipp

Beilstein J. Nanotechnol. 2015, 6, 293–299, doi:10.3762/bjnano.6.27

• nanoparticles are different depending on the fruit used for preparation. The green preparation process can result in individual nanoparticles with a very poor tendency to form aggregates with narrow gaps even when aggregation is forced by the addition of NaCl. This explains only modest enhancement factors for

• SERS, particularly also when excitation in the NIR is used as in many biological applications [20]. High local fields can be generated in small gaps between nanoparticles such as in aggregates [21][22][23]. The green preparation process using orange extract delivers mainly isolated silver particles and

• behavior of the green silver nanoparticles might be explained by the presence of other molecules on the surface of the particles related to plant materials introduced due to the green preparation, which prevent that particles come very close together and even touch each other. Moreover, these residual