在一个纳米管状蛋白质外套中,量身定制微米长的高完整性1D数组的超偏磁纳米粒子及其横向磁组装行为
Seunghyun Sim1,2, Daigo Miyajima1, Tatsuya Niwa3
1†RIKEN Center for Emergent Matter Science, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
Journal of the American Chemical Society
|April 1, 2015
概括
研究人员在纳米管中创建了微米长,一维的超偏磁铁氧化物纳米粒子 (SNPs) 阵列. 这些自组装结构展示了磁场诱导的横向组装,这种现象以前只能预测.
科学领域:
- 超分子化学 超分子化学
- 纳米技术 纳米技术
- 生物材料科学 生物材料科学
背景情况:
- 超偏磁铁氧化物纳米粒子 (SNPs) 提供了受控组装的潜力.
- 像GroEL这样的Chaperonin蛋白质为纳米粒子组织提供了一个支架.
- 实现可控的一维 (1D) 的纳米粒子阵列仍然是一个挑战.
研究的目的:
- 通过超分子聚合来定制微米长的1DSNP阵列.
- 为了研究含有SNP的纳米结构的磁场诱导组装.
- 实验验证纳米粒子阵列横向组装的理论预测.
主要方法:
- 一种GroEL突变体 (GroELMC) 的超分子聚合,复杂化与联体修饰的SNP.
- 使用Mg2+介导的协调键来形成纳米管.
- 应用0.5 T磁场来诱导1D SNP阵列的横向组合.
主要成果:
- 形成热力学稳定的微米长的纳米管,封装1D排列SNP (NTGroELSNP).
- 在磁场下观察NTGroELSNP纳米管的横向组装成厚的1D束.
- 在移除磁场后,可逆捆拆卸的演示.
- 对1D SNP数组的磁场诱导侧面组件的概念验证.
结论:
- 通过Mg2+介导的超分子聚合,可以在纳米管内精确地定制1D SNP阵列.
- 磁场可以可控地诱导这些1D纳米结构的横向组装.
- 这项工作为1D纳米粒子数组的横向组装提供了第一个实验证据.
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