Chen Xiuqiong, Yan Huiqiong, Sun Wei, Chen Guangying, Yu Changjiang, Feng Wen, Lin Qiang
Key Laboratory of Tropical Medicinal Plant Chemistry of Ministry of Education, College of Chemistry and Chemical Engineering, Hainan Normal University Haikou 571158 China
Key Laboratory of Water Pollution Treatment & Resource Reuse of Hainan Province, College of Chemistry and Chemical Engineering, Hainan Normal University Haikou 571158 Hainan China.
RSC Adv. 2018 Nov 13;8(66):38003-38012. doi: 10.1039/c8ra07117a. eCollection 2018 Nov 7.
To achieve the dispersion of the hydrophobic graphene (GR), the amphiphilic alginate caprylamide (ACA) was synthesized to fabricate electroactive Nafion/Mb-ACA-GR/CILE for the accurate determination of trichloroacetic acid (TCA). SEM observation, FT-IR and UV-Vis spectroscopic analysis indicated that ACA could tightly immobilize Mb and GR on the electrode surface by constructing biointerfaces, which not only provided Mb a suitable microenvironment to maintain its biological activity, but also shortened the distances between the active centers of Mb with carbon ionic liquid electrode (CILE), thus promoting the electron transfer rate. The electrochemical characterization of Nafion/Mb-ACA-GR/CILE showed that the direct electron transfer of Mb was realized on the modified electrode, which was attributed to the high electrical conductivity and excellent electrocatalytic activity of GR and good biocompatibility of ACA. Moreover, Nafion/Mb-ACA-GR/CILE exhibited good electrocatalytic activity towards TCA with the linear range from 2.5 to 47.3 mmol L and lower value of 8.3 mmol L. Moreover, the modified electrode also revealed good stability, reproducibility and accurate detection of tap-water, exhibiting great potential for the applications as the third-generation electrochemical biosensors.
为实现疏水性石墨烯（GR）的分散，合成了两亲性海藻酸辛酰胺（ACA），以制备用于准确测定三氯乙酸（TCA）的电活性Nafion/Mb-ACA-GR/碳离子液体电极（CILE）。扫描电子显微镜观察、傅里叶变换红外光谱和紫外-可见光谱分析表明，ACA可通过构建生物界面将肌红蛋白（Mb）和GR紧密固定在电极表面，这不仅为Mb提供了合适的微环境以维持其生物活性，还缩短了Mb的活性中心与碳离子液体电极之间的距离，从而提高了电子转移速率。Nafion/Mb-ACA-GR/CILE的电化学表征表明，Mb在修饰电极上实现了直接电子转移，这归因于GR的高电导率和优异的电催化活性以及ACA良好的生物相容性。此外，Nafion/Mb-ACA-GR/CILE对TCA表现出良好的电催化活性，线性范围为2.5至47.3 mmol/L，检测下限为8.3 mmol/L。此外，修饰电极还具有良好的稳定性、重现性，对自来水检测准确，作为第三代电化学生物传感器具有巨大的应用潜力。
