Agricultural & Biological Engineering, University of Florida, USA.
Agricultural & Biological Engineering, University of Florida, USA; Food Engineering, Universidad del Valle, Colombia.
Biosens Bioelectron. 2014 Aug 15;58:179-85. doi: 10.1016/j.bios.2014.02.021. Epub 2014 Feb 26.
Most graphene-metal nanocomposites for biosensing are formed using noble metals. Recently, development of nanocomposites using rare earth metals has gained much attention. This paper reports on the development of a nanoceria-nanoplatinum-graphene hybrid nanocomposite as a base transducing layer for mediator-free enzymatic biosensors. The hybrid nanocomposite was shown to improve detection of superoxide or hydrogen peroxide when compared to other carbon-metal hybrid nanocomposites. Based on this finding, the nanocomposite was applied for biosensing by adding either a peroxide-producing oxidase (glucose oxidase), or a superoxide-producing oxidase (xanthine oxidase). Material analysis indicated that nanoceria and nanoplatinum were equally distributed along the surface of the hybrid material, ensuring detection of either superoxide or hydrogen peroxide produced by oxidase activity. Glucose biosensors demonstrated a sensitivity (66.2±2.6μAmM(-1)cm(-2)), response time (6.3±3.4s), and limit of detection (1.3±0.6μM) that were comparable to other graphene-mediated electrodes in the current literature. Remarkably, XOD biosensor sensitivity (1164±332μAmM(-1)), response time (5.0±1.5s), and limit of detection (0.2±0.1μM) were higher than any reported biosensors using similar metal-decorated carbon nanomaterials. This material is the first demonstration of a highly efficient, diverse nanoceria/nanoplatinum/graphene hybrid nanocomposite for biosensing.
大多数用于生物传感的石墨烯-金属纳米复合材料都是使用贵金属形成的。最近，使用稀土金属开发纳米复合材料引起了广泛关注。本文报道了一种纳米氧化铈-纳米铂-石墨烯杂化纳米复合材料的开发，作为无介体酶生物传感器的基本转换层。与其他碳-金属杂化纳米复合材料相比，该杂化纳米复合材料显示出对超氧化物或过氧化氢的检测改善。基于这一发现，通过添加过氧化物产生酶（葡萄糖氧化酶）或超氧化物产生酶（黄嘌呤氧化酶），将该纳米复合材料应用于生物传感。材料分析表明，纳米氧化铈和纳米铂均匀分布在杂化材料的表面上，从而确保检测到酶活性产生的超氧化物或过氧化氢。葡萄糖生物传感器的灵敏度（66.2±2.6μAmM(-1)cm(-2)）、响应时间（6.3±3.4s）和检测限（1.3±0.6μM）与当前文献中其他基于石墨烯的电极相当。值得注意的是，XOD 生物传感器的灵敏度（1164±332μAmM(-1)）、响应时间（5.0±1.5s）和检测限（0.2±0.1μM）均高于使用类似金属修饰碳纳米材料的任何报道的生物传感器。该材料首次证明了高效、多样化的纳米氧化铈/纳米铂/石墨烯杂化纳米复合材料在生物传感中的应用。
