In this paper, we report the synthesis of a carboxyl-functionalized polypyrrole derivative, a poly(pyrrole-N-propanoic acid) (PPPA) film, by electrochemical polymerization, and the investigation of its basic properties via traditional characterization techniques such as confocal-Raman, FTIR, SEM, AFM, UV−vis, fluorescence microscopy, and contact-angle measurements. The experimental data show that the as-prepared PPPA film exhibits a hydrophilic nanoporous structure, abundant −COOH functional groups in the polymer backbone, and high fluorescent emission under laser excitation. On the basis of these unique properties, further experiments were conducted to demonstrate three potential applications of the PPPA film in chemical and biological sensors: a permeable and permselective membrane, a membrane with specific recognition sites for biomolecule immobilization, and a fluorescent conjugated polymer for amplification of fluorescence quenching. Specifically, the permeability and permselectivity of ion species through the PPPA film are detected by means of rotating-disk-electrode voltammetry; the specific recognition sites on the film surface are confirmed with protein immobilization, and the amplification of fluorescence quenching is measured by the addition of a quenching agent with fluorescence microscopy. The results are in good agreement with our expectations.

中文翻译：

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功能化的聚吡咯膜：合成，表征和在化学和生物传感器中的潜在应用。

在本文中，我们报告了羧基官能化的聚吡咯衍生物，即聚（吡咯-N-丙酸）（PPPA）膜，通过电化学聚合，并通过传统的表征技术（例如共聚焦拉曼光谱，FTIR，SEM，AFM，UV-vis，荧光显微镜和接触角测量）研究其基本性能。实验数据表明，所制备的PPPA薄膜表现出亲水性的纳米孔结构，聚合物主链中丰富的-COOH官能团以及在激光激发下的高荧光发射。基于这些独特的特性，进行了进一步的实验，以证明PPPA膜在化学和生物传感器中的三种潜在应用：可渗透和选择性渗透的膜，具有用于生物分子固定的特定识别位点的膜以及用于扩增的荧光共轭聚合物荧光猝灭。具体来说，通过旋转盘电极伏安法检测离子穿过PPPA膜的渗透性和选择性。通过固定蛋白质来确认膜表面上的特定识别位点，并通过在荧光显微镜下添加猝灭剂来测量荧光猝灭的扩增。结果与我们的预期高度吻合。