De Sriparna, Mohanty Smita, Nayak Sanjay Kumar
Central Institute of Plastics Engineering and Technology (CIPET), Chennai, India.
Bioprocess Biosyst Eng. 2015 Sep;38(9):1671-83. doi: 10.1007/s00449-015-1408-5. Epub 2015 May 17.
The present study summarizes the designing of a green transducer phase based on nano-cerium oxide (CeO2) decorated reduced graphene oxide (RGO) reinforced chitosan nanocomposites as an effective enzyme immobilizer and bio-sensing matrix for glucose analyte. Also, it scrutinizes the biocompatibility and cell viability of the synthesized nanohybrid with human fibroblastic macrophage cell line. CeO2 nanoparticles (NPs) were successfully grown on graphene nanosheet in the presence of cationic surfactant followed by facile hydrothermal treatment. The eventual growth of synthesized CeO2 nanocrystals on the graphene layer was confirmed from X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman analysis. The biocompatibility of the synthesized nanohybrid was also evident from the MTT assay. Glucose oxidase (GOx) was employed on the green polymer nanocomposites modified FTO electrode to fabricate an enzymatic bioelectrode. The electroanalytical response of the GOx/nano-CeO2/RGO/CS/FTO bioelectrode towards electrooxidation of glucose analyte was investigated by electrochemical impedance (EIS) and cyclic voltammetry (CV) study. The resulting biosensor exhibited a good electrochemical response to glucose within the linear detection range of 0.05-6.5 mM with a low detection limit of 2 μM and a sensitivity of 7.198 μA mM(-1) cm(-2). The bioelectrode also showed good shelf life (~10 weeks) and negligible interfering ability under controlled environment. The obtained results indicate that nano-CeO2/RGO nanohybrid based chitosan nanocomposites achieve a biocompatible biosensing platform for effective enzyme immobilization due to the excellent synergistic effects between the CeO2 nanoparticles and graphene sheet.
本研究总结了基于纳米氧化铈（CeO2）修饰的还原氧化石墨烯（RGO）增强壳聚糖纳米复合材料设计的绿色传感器相，该复合材料作为葡萄糖分析物的有效酶固定剂和生物传感基质。此外，还研究了合成的纳米杂化物与人成纤维细胞巨噬细胞系的生物相容性和细胞活力。在阳离子表面活性剂存在下，CeO2纳米颗粒（NPs）成功生长在石墨烯纳米片上，随后进行简便的水热处理。通过X射线衍射（XRD）、透射电子显微镜（TEM）和拉曼分析证实了合成的CeO2纳米晶体最终在石墨烯层上的生长。MTT分析也表明了合成的纳米杂化物的生物相容性。将葡萄糖氧化酶（GOx）应用于绿色聚合物纳米复合材料修饰的FTO电极上，制备了一种酶生物电极。通过电化学阻抗（EIS）和循环伏安法（CV）研究了GOx/纳米CeO2/RGO/CS/FTO生物电极对葡萄糖分析物电氧化的电分析响应。所得生物传感器在0.05 - 6.5 mM的线性检测范围内对葡萄糖表现出良好的电化学响应，检测限低至2 μM，灵敏度为7.198 μA mM(-1) cm(-2)。该生物电极在受控环境下还显示出良好的保质期（约10周）和可忽略不计的干扰能力。所得结果表明，由于CeO2纳米颗粒与石墨烯片之间的优异协同效应，基于纳米CeO2/RGO纳米杂化物的壳聚糖纳米复合材料实现了用于有效酶固定的生物相容性生物传感平台。
