Department of Chemical Engineering, Delft University of Technology, van der Maasweg 9, 2629 HZ Delft, The Netherlands.
Nat Commun. 2017 Jul 5;8:15317. doi: 10.1038/ncomms15317.
Self-assembly provides access to a variety of molecular materials, yet spatial control over structure formation remains difficult to achieve. Here we show how reaction-diffusion (RD) can be coupled to a molecular self-assembly process to generate macroscopic free-standing objects with control over shape, size, and functionality. In RD, two or more reactants diffuse from different positions to give rise to spatially defined structures on reaction. We demonstrate that RD can be used to locally control formation and self-assembly of hydrazone molecular gelators from their non-assembling precursors, leading to soft, free-standing hydrogel objects with sizes ranging from several hundred micrometres up to centimeters. Different chemical functionalities and gradients can easily be integrated in the hydrogel objects by using different reactants. Our methodology, together with the vast range of organic reactions and self-assembling building blocks, provides a general approach towards the programmed fabrication of soft microscale objects with controlled functionality and shape.
自组装为获取各种分子材料提供了途径，但对于结构形成的空间控制仍然难以实现。在这里，我们展示了如何将反应-扩散（RD）与分子自组装过程相结合，从而生成具有形状、大小和功能控制的宏观独立物体。在 RD 中，两个或更多的反应物从不同位置扩散，从而在反应时产生空间限定的结构。我们证明，RD 可用于局部控制腙分子凝胶剂从其非组装前体的形成和自组装，从而生成软的、独立的水凝胶物体，其尺寸从几百微米到几厘米不等。通过使用不同的反应物，很容易在水凝胶物体中集成不同的化学功能和梯度。我们的方法，结合了广泛的有机反应和自组装构建块，为具有受控功能和形状的软微尺度物体的编程制造提供了一种通用方法。
