Silicification of Peptide-Coated Silver Nanoparticles—A Biomimetic Soft Chemistry Approach toward Chiral Hybrid Core−Shell Materials
详细信息 查看全文
- 作者：Philipp Graf ; Alexandre Mantion ; Andrea Haase ; Andreas F. Thünemann ; Admir Mašić ; Wolfgang Meier ; Andreas Luch ; Andreas Taubert
- 刊名：ACS Nano
- 出版年：2011
- 出版时间：February 22, 2011
- 年：2011
- 卷：5
- 期：2
- 页码：820-833
- 全文大小：1346K
- 年卷期：0
- ISSN：1936-086X
文摘
Silica and silver nanoparticles are relevant materials for new applications in optics, medicine, and analytical chemistry. We have previously reported the synthesis of pH responsive, peptide-templated, chiral silver nanoparticles. The current report shows that peptide-stabilized nanoparticles can easily be coated with a silica shell by exploiting the ability of the peptide coating to hydrolyze silica precursors such as TEOS or TMOS. The resulting silica layer protects the nanoparticles from chemical etching, allows their inclusion in other materials, and renders them biocompatible. Using electron and atomic force microscopy, we show that the silica shell thickness and the particle aggregation can be controlled simply by the reaction time. Small-angle X ray scattering confirms the Ag/peptide@silica core−shell structure. UV−vis and circular dichroism spectroscopy prove the conservation of the silver nanoparticle chirality upon silicification. Biological tests show that the biocompatibility in simple bacterial systems is significantly improved once a silica layer is deposited on the silver particles.