XLIII Annual Meeting of SBBq Foz do Iguaçu, PR, Brazil, May 17th to 20th, 2014 Meringue, eggnog and omelette: Eggs for one step green synthesis of stable and biocompatible gold nanoparticles Tofanello, A.1, Nantes, I.L.1 1Nanoestruturas para Biologia e Materiais Avançados (NanoBioMAv), Centro de Ciências Naturais e Humanas, Universidade Federal do ABC, Santo André, SP, Brazil Introduction The use of biomolecules as templates, reducing and stabilizing agents for controlled synthesis of metallic nanoparticles has crescent interest. The advantages are: mild pH and temperature, use of water as solvent, fastness and stabilization concomitant with the synthesis1. In this regard, egg proteins have high affinity for metal ions facilitating nucleation of NPs. Objective: The objective is to develop a low cost, green method of gold NP synthesis by using egg components as reducing and stabilizing agents. Also, the differences in the composition of egg components contribute for the comprehension of the mechanisms involved in the synthesis of gold NPs by biomolecules. MATERIAL and METHODS: In a typical procedure, 300 μL egg white extract was fully dissolved in 300 μL phosphate buffer (pH=5; 7,2 and 9) in the presence of gold salt solution. RESULTS AND DISCUSSION: Egg yolk was the most efficient egg component to fast (48 h) production of smaller gold NPs (around 20 nm diameter). Egg white and the mixture of egg white and yolk produced gold NPs with 50 nm diameter after 72 h incubation. The structure and functional groups of egg white albumin and yolk proteins (phosvitin, lipovitelin and livitin) associated to a high content of cholesterol and phosphatidylcholine provides peculiar conditions for reduction of gold ions and NP nucleation. Furthermore, after NP formation the recovering of their surfaces by the biomolecules provides stabilization and biocompatibility. CONCLUSION: The egg components are useful for a green and one step method for the synthesis of gold NPs. In addition these studies bring lights about the contribution of protein structure and sequence as well as the association with lipids in supramolecular arrangements for the control of NP size and form. Key words: gold nanoparticles, albumin, egg white and yolk Supported by FAPESP, CNPq and CAPES. 1 Li et al, Int. J. of Nanomedicine, 2101-2107, 2012. .