Programmable shape-shifting micelles.
Programmable shape-shifting micelles.
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DOI：
10.1002/anie.201000265
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发表时间：
2010-07-12
期刊：
影响因子：
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通讯作者：
Gianneschi NC
中科院分区：
文献类型：
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作者：
Chien MP;Rush AM;Thompson MP;Gianneschi NC
预期响应于刺激而在形态上经历可逆和确定的变化的纳米级颗粒在一系列应用中具有广泛的用途，包括靶向药物递送、检测策略、软模板和自修复材料。迄今为止，具有这些特性的可编程材料尚未报道，尽管有许多刺激响应性软纳米颗粒和胶束的优雅例子。[1 - 11]受DNA在纳米技术中作为信息分子的效用的启发，[12 - 20]我们在此报道了DNA编码的聚合物材料，其能够原位控制、选择性、可逆和用户定义的形态变化。该设计基于由一组新颖的两亲性DNA刷共聚物形成的聚合物胶束（图1）。[16通过利用DNA的序列选择性识别特性，[22]及其作为选择性酶促裂解底物的性能，[23，24]可以以几种模式读取和操纵存储在胶束壳中的信息，导致形态和颗粒大小的巨大变化。DNA的设计原理-程序化胶束形态是基于控制两亲嵌段共聚物聚集的规则。[25简而言之，组装的两亲物的相（形状、尺寸、总体形态）由它们的几何结构和静电控制。[27]因此，假设DNA-刷共聚物两亲物将组装成具有由序列选择性相互作用控制的形态的胶束，这允许操纵胶束壳中的空间和静电排斥的大小。两亲物几何结构的变化如图1所示;较大的锥角产生较高的表面曲率聚集体（即球体）。为了证明DNA程序化胶束相变的概念，选择了三种类型的序列选择性相互作用：1）酶促切割，2）互补单链DNA（ssDNA）的等温杂交，和3）DNA双链体的热熔融和退火。
Nanoscale particles that undergo reversible and defined changes in morphology in response to stimuli are expected to have broad utility in a range of applications, including targeted drug delivery, detection strategies, soft templates, and self-healing materials. To date, programmable materials with these properties have not been reported, despite the many elegant examples of stimuli-responsive soft nanoparticles and micelles.[1–11] Inspired by the utility of DNA as an informational molecule in nanotechnology,[12–20] we report herein DNA-encoded polymeric materials that are capable of in situ controlled, selective, reversible, and user-defined shifts in morphology. The design is based on polymeric micelles formed from a novel set of amphiphilic DNA-brush copolymers (Figure 1).[16, 21] By utilizing the sequence-selective recognition properties of DNA,[22] and its performance as a substrate for selective enzymatic cleavage,[23, 24] information stored in the micelle shell may be read and manipulated in several modes, causing dramatic changes in morphology and particle size.The design rationale for DNA-programmed micelle morphology is based on rules that govern the aggregation of amphiphilic block copolymers.[25, 26] Briefly, the phase (shape, size, overall morphology) of assembled amphiphiles is controlled by their geometric structure and electrostatics.[27] Therefore, it was hypothesized that DNA-brush copolymer amphiphiles would assemble into micelles with morphologies that are governed by sequence-selective interactions, which allow manipulation of the magnitude of steric and electrostatic repulsions in the micelle shells. Changes in geometric structure of the amphiphile are shown in Figure 1; larger cone angles give higher surface curvature aggregates (ie, spheres). To demonstrate the concept of DNA-programmed micelle phase transition, three types of sequence-selective interactions were chosen: 1) enzymatic cleavage, 2) isothermal hybridization of complementary single-stranded DNA (ssDNA), and 3) thermal melting and annealing of DNA duplexes.