Probing interfacial equilibration in microsphere crystals formed by DNA-directed assembly

被引：67

作者：

Kim, Anthony J. ^{[1
]}

Scarlett, Raynaldo ^{[1
]}

Biancaniello, Paul L. ^{[2
]}

Sinno, Talid ^{[1
]}

Crocker, John C. ^{[1
]}

机构：

[1] Univ Penn, Dept Chem & Biomol Engn, Philadelphia, PA 19104 USA

[2] Univ Penn, Dept Phys & Astron, Philadelphia, PA 19104 USA

来源：

NATURE MATERIALS | 2009年 / 8卷 / 01期

基金：

美国国家科学基金会;

关键词：

NEAREST-NEIGHBOR THERMODYNAMICS; CRYSTALLIZATION; COLLOIDS; DIFFUSION; STABILITY; POLYMER; DESIGN;

D O I：

10.1038/NMAT2338

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

DNA is the premier material for directing nanoscale self-assembly, having been used to produce many complex forms(1-4). Recently, DNA has been used to direct colloids(5,6) and nanoparticles(7,8) into novel crystalline structures, providing a potential route to fabricating meta-materials(9) with unique optical properties. Although theory(10-12) has sought the crystal phases that minimize total free energy, kinetic barriers(13) remain essentially unstudied. Here we study interfacial equilibration in a DNA-directed microsphere self-assembly system(5,6,14) and carry out corresponding detailed simulations. We introduce a single-nucleotide difference in the DNA strands on two mixed microsphere species, which generates a free-energy penalty(5,15,16) for inserting 'impurity' spheres into a 'host' sphere crystal, resulting in a reproducible segregation coefficient. Comparison with simulation reveals that, under our experimental conditions, particles can equilibrate only with a few nearest neighbours before burial by the growth front, posing a potential impediment to the growth of complex structures.

引用

页码：52 / 55

页数：4