Folic acid-polydopamine nanofibers show enhanced ordered-stacking via π-π interactions
Folic acid-polydopamine nanofibers show enhanced ordered-stacking via π-π interactions
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DOI：
10.1039/c5sm00732a
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发表时间：
2015-01-01
期刊：
影响因子：
3.4
通讯作者：
Jin, Zhaoxia
中科院分区：
文献类型：
--
作者：
Fan, Hailong;Yu, Xiang;Jin, Zhaoxia
最近的研究表明，聚多巴胺和合成的真黑素是光电生物材料，其中有序堆叠的低聚物组成的一维聚集体已被提出作为独特的有机半导体。然而，改善聚多巴胺纳米结构中低聚物的有序堆叠是一个很大的挑战。在此，我们首先展示了叶酸分子如何通过调节低聚物的π-π相互作用来影响聚多巴胺的形态和纳米结构。MALDI-TOF质谱显示，卟啉样四聚体是叶酸-聚多巴胺（FA-PDA）纳米纤维的特征。X射线衍射结合模拟研究表明，这些低聚物有利于聚集成石墨状有序的纳米结构，通过强π-π相互作用。高分辨率TEM表征的FA-PDA杂化物表明，在FA-PDA纳米纤维中，类石墨结构域的尺寸超过100 nm。叶酸在聚多巴胺中的添加增强了低聚物在其纳米结构中的有序堆叠。我们的研究进一步揭示了FA-PDA杂化材料的结构与性能关系的奥秘。为通过低聚物结构的设计和选择来优化PDA的性能奠定了基础。
Recent research has indicated that polydopamine and synthetic eumelanins are optoelectronic biomaterials in which one-dimensional aggregates composed of ordered-stacking oligomers have been proposed as unique organic semiconductors. However, improving the ordered-stacking of oligomers in polydopamine nanostructures is a big challenge. Herein, we first demonstrate how folic acid molecules influence the morphology and nanostructure of polydopamine via tuning the pi-pi interactions of oligomers. MALDI-TOF mass spectrometry reveals that porphyrin-like tetramers are characteristic of folic acid-polydopamine (FA-PDA) nanofibers. X-ray diffraction combined with simulation studies indicate that these oligomers favour aggregation into graphite-like ordered nanostructures via strong pi-pi interactions. High-resolution TEM characterization of carbonized FA-PDA hybrids show that in FA-PDA nanofibers the size of the graphite-like domains is over 100 nm. The addition of folic acid in polydopamine enhances the ordered stacking of oligomers in its nanostructure. Our study steps forward to discover the mystery of the structure-property relationship of FA-PDA hybrids. It paves a way to optimize the properties of PDA through the design and selection of oligomer structures.