Almeida Luís C, Zeferino Jorge F, Branco Clara, Squillaci Guiseppe, Morana Alessandra, Santos Romana, Ihalainen Petri, Sobhana Liji, Correia Jorge P, Viana Ana S
Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
Centro de Química Estrutural, Institute of Molecular Sciences, Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal.
Bioelectrochemistry. 2025 Feb;161:108826. doi: 10.1016/j.bioelechem.2024.108826. Epub 2024 Sep 20.
The successful fabrication of biosensors is greatly limited by the immobilization of their bioreceptor, thus we propose a facile and reproducible two-step method to modify graphite electrodes with a bacterial laccase, relying on a fast and controllable potentiostatic process to coat graphite surfaces with biomolecule-compatible thin films of polynorepinephrine (ePNE) and polydopamine (ePDA). Both polymers, synthesized with a similar thickness, were functionalized with bacterial laccase, displaying distinct electrochemical transducing behaviours at pH 5.0 and 7.0. ePNE layer enables adequate electron transfer of anionic and cationic species in acidic and neutral media, whereas transduction across ePDA strongly depends on pH and redox probe charge. ePNE stands out by improving the amperometric responses of the biosensing interface towards a phenolic acid (gallic acid) and a flavonoid (catechin), in respect to ePDA. The optimal graphite/ePNE/laccase interface outperforms biosensing interfaces based on fungal laccases at neutral pH, displaying detection sensitivities of 104 and 14.4 µA cm mMfor gallic acid and catechin, respectively. The fine synthetic control of the ePNE bio-inspired transduction layer and the use of an alkaliphilic bacterial laccase enabled the construction of an amperometric biosensing interface with extended pH range of polyphenols detection present in food products and agro-industrial waste.
生物传感器的成功制备在很大程度上受到其生物受体固定化的限制，因此我们提出了一种简便且可重复的两步法，用于用细菌漆酶修饰石墨电极，该方法依赖于快速且可控的恒电位过程，以用聚去甲肾上腺素（ePNE）和聚多巴胺（ePDA）的生物分子兼容薄膜覆盖石墨表面。两种聚合物合成时厚度相似，均用细菌漆酶进行了功能化，在pH 5.0和7.0时表现出不同的电化学传感行为。ePNE层能使阴离子和阳离子物种在酸性和中性介质中实现充分的电子转移，而通过ePDA的传感则强烈依赖于pH值和氧化还原探针电荷。相较于ePDA，ePNE在改善生物传感界面对于酚酸（没食子酸）和类黄酮（儿茶素）的安培响应方面表现突出。在中性pH条件下，最优的石墨/ePNE/漆酶界面优于基于真菌漆酶的生物传感界面，对没食子酸和儿茶素的检测灵敏度分别为104和14.4 μA cm mM。对ePNE生物启发传感层的精细合成控制以及嗜碱细菌漆酶的使用，使得能够构建一个安培生物传感界面，用于检测食品和农业工业废弃物中多酚的pH范围得以扩展。
