Synthesis of CdSe Quantum Dots Using Fusarium oxysporum

Takaaki Yamaguchi; Yoshijiro Tsuruda; Tomohiro Furukawa; Lumi Negishi; Yuki Imura; Shohei Sakuda; Etsuro Yoshimura; Michio Suzuki

doi:10.3390/ma9100855

Synthesis of CdSe Quantum Dots Using Fusarium oxysporum

Materials (Basel). 2016 Oct 20;9(10):855. doi: 10.3390/ma9100855.

Authors

Takaaki Yamaguchi¹, Yoshijiro Tsuruda², Tomohiro Furukawa³, Lumi Negishi⁴, Yuki Imura⁵, Shohei Sakuda⁶, Etsuro Yoshimura^{7

8}, Michio Suzuki⁹

Affiliations

¹ Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. kenmei.takaaki@gmail.com.
² Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. 2.obv.0627@gmail.com.
³ Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. mountainXTC@live.jp.
⁴ Institute of Molecular and Cellular Biosciences, the University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan. lnegishi@iam.u-tokyo.ac.jp.
⁵ Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. aimuray@mail.ecc.u-tokyo.ac.jp.
⁶ Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. asakuda@mail.ecc.u-tokyo.ac.jp.
⁷ Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. ayoshim@mail.ecc.u-tokyo.ac.jp.
⁸ Faculty of Liberal Arts, the Open University of Japan, 2-11 Wakaba, Mishima-ku, Chiba-city, Chiba 261-8586, Japan. ayoshim@mail.ecc.u-tokyo.ac.jp.
⁹ Department of Applied Biological Chemistry, Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan. amichiwo@mail.ecc.u-tokyo.ac.jp.

Abstract

CdSe quantum dots are often used in industry as fluorescent materials. In this study, CdSe quantum dots were synthesized using Fusarium oxysporum. The cadmium and selenium concentration, pH, and temperature for the culture of F. oxysporum (Fusarium oxysporum) were optimized for the synthesis, and the CdSe quantum dots obtained from the mycelial cells of F. oxysporum were observed by transmission electron microscopy. Ultra-thin sections of F. oxysporum showed that the CdSe quantum dots were precipitated in the intracellular space, indicating that cadmium and selenium ions were incorporated into the cell and that the quantum dots were synthesized with intracellular metabolites. To reveal differences in F. oxysporum metabolism, cell extracts of F. oxysporum, before and after CdSe synthesis, were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results suggested that the amount of superoxide dismutase (SOD) decreased after CdSe synthesis. Fluorescence microscopy revealed that cytoplasmic superoxide increased significantly after CdSe synthesis. The accumulation of superoxide may increase the expression of various metabolites that play a role in reducing Se⁴⁺ to Se^2- and inhibit the aggregation of CdSe to make nanoparticles.

Keywords: CdSe; Fusarium oxysporum; quantum dot; superoxide dismutase.