Biological synthesis of quantum dots （QDs） as an environmental-friendly and facile preparation method has attracted increasing interests. However, it is difficult to distinguish the roles ofbio-thiols in QDs synthes...Biological synthesis of quantum dots （QDs） as an environmental-friendly and facile preparation method has attracted increasing interests. However, it is difficult to distinguish the roles ofbio-thiols in QDs synthesis process because of the complex nature in organisms. In this work, the CdSe QDs synthesis conditions in organisms were reconstructed by using a simplified in vitro approach to uncover the roles of two small bio-thiols in the QDs formation. CdSe QDs were synthesized with glutathione （GSH） and L-cysteine （Cys） respectively. Compared with Cys at the same molar concentration, the CdSe QDs synthesized by GSH had a larger and broader particle size distribution with improved optical properties and crystal structure. Furthermore, quantum chemical calculations indicate that the stronger Cd^2＋ binding capacity ofGSH contributed a lot to the CdSe QDs formation despite ofthe greater capability Cys for selenite reduction. This work clearly demonstrates the different roles of small thiols in the Cd2^＋- stabilization in the environment and biomimetic QDs synthesis process.展开更多
基金Acknowledgements The work was supported by the National Natural Science Foundation of China （Grant No. 21590812）, and the Collaborative Innovation Center of Suzhou Nano Science and Technology.
文摘Biological synthesis of quantum dots （QDs） as an environmental-friendly and facile preparation method has attracted increasing interests. However, it is difficult to distinguish the roles ofbio-thiols in QDs synthesis process because of the complex nature in organisms. In this work, the CdSe QDs synthesis conditions in organisms were reconstructed by using a simplified in vitro approach to uncover the roles of two small bio-thiols in the QDs formation. CdSe QDs were synthesized with glutathione （GSH） and L-cysteine （Cys） respectively. Compared with Cys at the same molar concentration, the CdSe QDs synthesized by GSH had a larger and broader particle size distribution with improved optical properties and crystal structure. Furthermore, quantum chemical calculations indicate that the stronger Cd^2＋ binding capacity ofGSH contributed a lot to the CdSe QDs formation despite ofthe greater capability Cys for selenite reduction. This work clearly demonstrates the different roles of small thiols in the Cd2^＋- stabilization in the environment and biomimetic QDs synthesis process.
