Unravelling the nature of the spongy dark material in aged Turkevich gold 10 nanoparticles colloidal solutions by CytoViva (R) dark-field imaging and HRTEM analysis

Author(s)

de Melo, Fernando Menegatti ^[1] ; Uchiyama, Mayara Klimuk ^[1] ; Nakamura, Marcelo ^[1] ; Kawassaki, Rodrigo Ken ^[1] ; Taborda, Carlos Pelleschi ^[2] ; Toma, Henrique Eisi ^[1]

Affiliation

^[1] Univ Sao Paulo, Chem Inst, BR-05508000 Sao Paulo, SP - Brazil

^[2] Univ Sao Paulo, Biomed Sci Inst, BR-05508900 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: Micron; v. 121, p. 21-25, JUN 2019.
• Web of Science Citations: 1

Abstract

Turkevich gold nanoparticles colloidal solutions undergo further changes after ageing for several weeks or months, and in most cases a spongy dark material can be observed suspended in the red solution. CytoViva (R) dark-field microscopy images and high resolution transmission electron micrographys (HRTEM) of the strange body played a central role and revealed a fibrous structure, consistent with cellulose, as commonly found in the cell-walls of many fungi. Surprisingly, the interior of the fibers are filled with gold nanoparticles, responsible for the high contrasting images obtained in this work. The fungi were replicated in the laboratory, characterized by Infrared Microscopy (FTIR) and revealed an ability to grow in gold-citrate media, even in dark and anaerobical conditions. (AU)

• FAPESP's process: 13/24725-4 - Supramolecular chemistry and nanotechnology
• Grantee: Henrique Eisi Toma
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 17/09469-2 - Development of chiral plasmonic systems to use as sensors, light propagation and molecular information
• Grantee: Vitor de Moraes Zamarion
• Support Opportunities: Regular Research Grants