Center for Bio/Molecular Science & Engineering, US Naval Research Laboratory, Washington, D.C. 20375, United States.
J Am Chem Soc. 2021 Mar 3;143(8):3094-3103. doi: 10.1021/jacs.0c10465. Epub 2021 Feb 18.
Commonly known as a skin pigment, melanin has a vital role in UV radiation protection, primarily acting as a radical scavenger. However, a lesser known natural property of melanin, observed in some melanized organisms, is its capacity to adsorb toxins, including metals and organic molecules. Inspired by this, we set out to generate a synthetic porous melanin that would pave the way to enhancing the natural adsorbent properties of melanin and melanin-like materials. Here, we developed a method for the synthesis of porous polydopamine-based melanin utilizing a mesoporous silica (MS) nanoparticle template and characterized its physical properties. Through the oxidative polymerization of dopamine, followed by the etching of silica, we generated synthetic porous melanin (SPM) with the highest measured surface area of any known polydopamine-based material. The prepared SPM was effective for the uptake of various gases and organophosphate toxins, with the material exhibiting high selectivity for CO over CH and high potential for ammonia capture. Given the demonstrated advantages provided by synthetic porous melanin and melanin's role as an adsorbent in nature, we anticipate the discovery of porous analogues in biological systems.
通常被称为皮肤色素，黑色素在紫外线辐射防护中起着至关重要的作用，主要作为自由基清除剂。然而，黑色素的一个不太为人知的自然特性，在一些黑色素化的生物体中观察到，是它吸附毒素的能力，包括金属和有机分子。受此启发，我们着手制造一种合成多孔黑色素，为增强黑色素和类黑色素材料的天然吸附特性铺平道路。在这里，我们开发了一种利用介孔二氧化硅（MS）纳米颗粒模板合成基于聚多巴胺的多孔黑色素的方法，并对其物理性质进行了表征。通过多巴胺的氧化聚合，然后是二氧化硅的刻蚀，我们生成了具有任何已知基于聚多巴胺材料中最高表面积的合成多孔黑色素（SPM）。所制备的 SPM 对各种气体和有机磷毒素的吸收有效，该材料对 CO 表现出高于 CH 的高选择性，并且对氨的捕获具有高潜力。鉴于合成多孔黑色素所提供的优势以及黑色素在自然界中作为吸附剂的作用，我们预计在生物系统中会发现多孔类似物。
