Department of Chemistry, Indian Institute of Technology Tirupati, Settipalli Post, Tirupati - 517506, Andhra Pradesh, India.
J Mater Chem B. 2021 Apr 28;9(16):3523-3532. doi: 10.1039/d1tb00221j.
Copper phosphate nanoflowers (CuPNFs) have been synthesized in the presence of different aromatic phenanthroline derivatives (Ln), leading to inorganic-organic hybrid materials (Ln-CuPNFs). Studies revealed that the morphology of nanoflowers varies as a function of the aromatic moiety present in the derivative, Ln (where 'n' corresponds to phenyl, naphthyl, anthracenyl, and pyrenyl) used for coating the nanomaterial. Other noticeable changes were the increase in the size of the flower by ∼2-3 fold in the presence of these derivatives. In the absence of such aromatic phenanthroline derivatives, i.e., the use of 1,10-phenanthroline-5-amine did not induce the formation of nanoflowers, suggesting that the organic derivatization used in the present study stabilizes the nanoflower structure. Nanoflowers were characterized using X-ray diffraction, Brunauer-Emmett-Teller (BET) isotherm, X-ray photoelectron spectroscopy, Raman and Infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy, thus covering a range of diffraction, spectroscopy, and microscopy techniques. Nanoflowers, Ln-CuPNFs, have been demonstrated for the oxidative reactions mimicking copper metalloenzymes in the presence and absence of hydrogen peroxide using different substrates. Thus, hybrid Ln-CuPNFs mediate the complete oxidation of o-phenylenediamine, dopamine, ascorbate oxidase, and terephthalic acid without causing much change in the morphology of the hybrid nanoflower material and with the retention of the activity supporting the hybrid as an acceptable enzyme mimicking material. Oxidation is mediated through hydroxyl radical formation and the order of the oxidative activity is pyrenyl > anthracenyl > naphthyl > phenyl for the inorganic-organic hybrid nanoflowers. The copper complex of pyrenyl-appended phenanthroline derivative also showed similar biomimetic activity.
磷酸铜纳米花（CuPNFs）在不同芳香菲咯啉衍生物（Ln）的存在下合成，导致无机-有机杂化材料（Ln-CuPNFs）。研究表明，纳米花的形态随衍生物中芳香部分的变化而变化，Ln（其中“n”对应于苯、萘、蒽和并五苯）用于涂覆纳米材料。其他明显的变化是在这些衍生物存在下，花的尺寸增加了约 2-3 倍。在没有这种芳香菲咯啉衍生物的情况下，即使用 1,10-菲咯啉-5-胺也不会诱导纳米花的形成，这表明本研究中使用的有机衍生化稳定了纳米花结构。使用 X 射线衍射、BET 等温线、X 射线光电子能谱、拉曼和红外光谱、扫描电子显微镜和透射电子显微镜对纳米花进行了表征，从而涵盖了一系列衍射、光谱和显微镜技术。纳米花、Ln-CuPNFs，在存在和不存在过氧化氢的情况下，模拟铜金属酶的氧化反应，使用不同的底物进行了证明。因此，杂化 Ln-CuPNFs 介导 o-苯二胺、多巴胺、抗坏血酸氧化酶和对苯二甲酸的完全氧化，而不会对杂化纳米花材料的形态造成太大变化，并保持支持杂化作为可接受的酶模拟材料的活性。氧化是通过羟基自由基的形成来介导的，对于无机-有机杂化纳米花，氧化活性的顺序为并五苯基>蒽基>萘基>苯基。并五苯基取代的菲咯啉衍生物的铜配合物也表现出类似的仿生活性。
