Nanochemistry and biotechnology

Melissa Officinalis L. leaf extract mediated synthesis of silver and gold nanoparticles
Mariychuk R.1, Smolková R.1, Eliašová A.1, 
Grishchenko L.M.2, Goriachko A.M.2, Diyuk V. E.2, Lisnyak V.V.2
1 Department of Ecology, Faculty of Humanities and Natural Sciences, University of Prešov in Prešov, 17th November Str. 1, 08001, Prešov, Slovakia.
E-mail: ruslan.mariychuk@unipo.sk
2 Taras Shevchenko National University of Kyiv, Volodymyrska Str. 62a, 01601 Kyiv, Ukraine.

Plant extracts are extensively involved in the synthesis of various nanoparticles as a mild, renewable, and non-toxic reducing agent and efficient stabilizer in the absence of toxic and hazardous compounds. The complex composition of plant extracts opens the possibility to control the shape of the resulting nanoparticles by directing their growth. 
Silver and gold nanoparticles have been synthesized using Melissa Officinalis L. leaf extracts prepared using different extraction conditions (composition of solvent and temperature). Additionally, the bioactive compounds present in each extract were studied using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) for indication of chemical groups that could be involved in the synthesis of nanoparticles. Here, a Folin-Ciocalteu (FC) assay showed that phenolic compounds play a clear role in the growth of nanoparticles.
The products of phytosynthesis depend on different factors, mainly on the conditions of the reaction, e.g., temperature, concentration. Besides, the reaction time, pH level, and extract constituents have the main effect and permit the formation and stability of the nanoparticles. That is why this study was focused on the search of preparation protocol of the nanocolloid solutions with a maximal yield of non-spherical nanoparticles. UV-Vis spectroscopy, SEM, EDS, elemental mapping, TEM, and AFM have been used to characterize Ag and Au nanoparticles.