Department of Chemistry, International Institute of Nanotechnology, Simpson-Querrey Institute, Chemistry of Life Processes Institute, Lurie Cancer Center, Northwestern University, Evanston, IL, 60208, USA.
Department of Biology, Evolution and Optics of Nanostructures Group, University of Ghent, 9000, Ghent, Belgium.
Angew Chem Int Ed Engl. 2021 Aug 2;60(32):17464-17471. doi: 10.1002/anie.202103447. Epub 2021 Jun 24.
Melanosomes in nature have diverse morphologies, including spheres, rods, and platelets. By contrast, shapes of synthetic melanins have been almost entirely limited to spherical nanoparticles with few exceptions produced by complex templated synthetic methods. Here, we report a non-templated method to access synthetic melanins with a variety of architectures including spheres, sheets, and platelets. Three 1,8-dihydroxynaphthalene dimers (4-4', 2-4' and 2-2') were used as self-assembling synthons. These dimers pack to form well-defined structures of varying morphologies depending on the isomer. Specifically, distinctive ellipsoidal platelets can be obtained using 4-4' dimers. Solid-state polymerization of the preorganized dimers generates polymeric synthetic melanins while maintaining the initial particle morphologies. This work provides a new route to anisotropic synthetic melanins, where the building blocks are preorganized into specific shapes, followed by solid-state polymerization.
天然的黑色素体具有多种形态，包括球体、棒体和薄片状。相比之下，合成黑色素的形态几乎完全局限于球形纳米颗粒，只有少数通过复杂的模板合成方法制备的例外。在这里，我们报告了一种非模板方法，可以获得具有多种结构的合成黑色素，包括球体、薄片和薄片状。三种 1,8-二羟基萘二聚体（4-4'、2-4'和 2-2'）被用作自组装单体。这些二聚体可以根据异构体的不同来组装形成具有不同形态的明确结构。具体来说，使用 4-4'二聚体可以获得独特的椭圆形薄片状。预组织的二聚体的固态聚合在保持初始颗粒形态的同时生成聚合的合成黑色素。这项工作为各向异性的合成黑色素提供了一种新途径，其中构建块被预组织成特定的形状，然后进行固态聚合。
