Synergetic Approach for Simple and Rapid Conjugation of Gold Nanoparticles with Oligonucleotides
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- 作者：Jiuxing Li ; Binqing Zhu ; Xiujie Yao ; Yicong Zhang ; Zhi Zhu ; Song Tu ; Shasha Jia ; Rudi Liu ; Huaizhi Kang ; Chaoyong James Yang
- 刊名：ACS Applied Materials & Interfaces
- 出版年：2014
- 出版时间：October 8, 2014
- 年：2014
- 卷：6
- 期：19
- 页码：16800-16807
- 全文大小：388K
- ISSN：1944-8252
文摘
Attaching thiolated DNA on gold nanoparticles (AuNPs) has been extremely important in nanobiotechnology because DNA鈥揂uNPs combine the programmability and molecular recognition properties of the biopolymers with the optical, thermal, and catalytic properties of the inorganic nanomaterials. However, current standard protocols to attach thiolated DNA on AuNPs involve time-consuming, tedious steps and do not perform well for large AuNPs, thereby greatly restricting applications of DNA鈥揂uNPs. Here we demonstrate a rapid and facile strategy to attach thiolated DNA on AuNPs based on the excellent stabilization effect of mPEG-SH on AuNPs. AuNPs are first protected by mPEG-SH in the presence of Tween 20, which results in excellent stability of AuNPs in high ionic strength environments and extreme pHs. A high concentration of NaCl can be applied to the mixture of DNA and AuNP directly, allowing highly efficient DNA attachment to the AuNP surface by minimizing electrostatic repulsion. The entire DNA loading process can be completed in 1.5 h with only a few simple steps. DNA-loaded AuNPs are stable for more than 2 weeks at room temperature, and they can precisely hybridize with the complementary sequence, which was applied to prepare core鈥搒atellite nanostructures. Moreover, cytotoxicity assay confirmed that the DNA鈥揂uNPs synthesized by this method exhibit lower cytotoxicity than those prepared by current standard methods. The proposed method provides a new way to stabilize AuNPs for rapid and facile loading thiolated DNA on AuNPs and will find wide applications in many areas requiring DNA鈥揂uNPs, including diagnosis, therapy, and imaging.