Zhang Jiali, Yu Hai, Harris Bradley, Zheng Yunbo, Celik Umit, Na Lan, Faller Roland, Chen Xi, Haudenschild Dominik R, Liu Gang-Yu
Department of Chemistry, University of California, Davis, California, 95616, United States.
Department of Chemical Engineering, University of California, Davis, California, 95616, United States.
J Phys Chem C Nanomater Interfaces. 2020 Mar 19;124(11):6405-6412. doi: 10.1021/acs.jpcc.9b11377. Epub 2020 Feb 23.
While self-assembly of molecules is relatively well-known and frequently utilized in chemical synthesis and material science, controlled assembly of molecules represents a new concept and approach. The present work demonstrates the concept of controlled molecular assembly using a non-spherical biomolecule, heparosan tetrasaccharide (MW = 1.099 kD). The key to controlled assembly is the fact that ultra-small solution droplets exhibit different evaporation dynamics from those of larger ones. Using an independently controlled microfluidic probe in an atomic force microscope, sub-femtoliter aqueous droplets containing designed molecules produce well-defined features with dimensions as small as tens of nanometers. The initial shape of the droplet and the concentration of solute within the droplet dictate the final assembly of molecules due to the ultrafast evaporation rate and dynamic spatial confinement of the droplets. The level of control demonstrated in this work brings us closer to programmable synthesis for chemistry and materials science which can be used to develop vehicles for drug delivery three-dimensional nanoprinting in additive manufacturing.
虽然分子的自组装在化学合成和材料科学中相对广为人知且经常被利用，但分子的可控组装却是一个新的概念和方法。目前的工作展示了使用非球形生物分子肝素四糖（分子量 = 1.099 kD）进行可控分子组装的概念。可控组装的关键在于超小溶液滴与较大溶液滴呈现出不同的蒸发动力学这一事实。在原子力显微镜中使用独立控制的微流体探针，含有设计分子的亚飞升级水滴会产生尺寸小至几十纳米的明确特征。由于液滴的超快蒸发速率和动态空间限制，液滴的初始形状和液滴内溶质的浓度决定了分子的最终组装。这项工作中展示的控制水平使我们更接近化学和材料科学的可编程合成，可用于开发药物递送载体以及增材制造中的三维纳米打印。
