Abstract

The rGO/hemoglobin/CdS biocomposite (rGO/Hb/CdS) were prepared via a simple route. The water-soluble rGO/CdS composite was synthesized in aqueous solution with a facile hydrothermal route. CdS nanoparticles (NPs) were anchored uniformly on the graphene nanosheets. With L-cysteine (Cys) as the molecular linker, the Hb molecules were then adsorbed onto the CdS NPs to produce the rGO/Hb/CdS biocomposite NPs. The rGO/Hb/CdS was characterized employing UV-vis spectroscopy, powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM). The electrochemical behaviors of rGO/Hb/CdS were characterized with cyclic voltammetric technique (CV). A pair of well-defined and quasi-reversible cyclic voltammetric peaks was observed. The cyclic voltammogram demonstrated the direct electron transfer of the Fe(III)/Fe(II) couple of Hb. The glassy carbon electrode (GCE) modified with rGO/Hb/CdS displays an excellent electrocatalytic response to the reduction of H₂O₂ with a detection limit of 6 × 10⁻⁷ M (S/N = 3). A linear calibration curve can be observed in the range of 1.9 × 10⁻⁶ ∼ 1.5 × 10⁻⁴ M.

摘要

rGO/血红蛋白/CdS 生物复合材料 (rGO/Hb/CdS)通过以下方式制备一条简单的路线。水溶性 rGO/CdS 复合材料是在水溶液中通过简便的水热路线合成的。CdS 纳米粒子 (NPs) 均匀地锚定在石墨烯纳米片上。以 L-半胱氨酸 (Cys) 作为分子接头，然后将 Hb 分子吸附到 CdS NPs 上以产生 rGO/Hb/CdS 生物复合材料 NPs。使用紫外-可见光谱、粉末 X 射线衍射 (XRD)、透射电子显微镜 (TEM) 和场发射扫描电子显微镜 (FE-SEM) 对 rGO/Hb/CdS 进行了表征。rGO/Hb/CdS的电化学行为采用循环伏安技术(CV)表征。观察到一对定义明确且准可逆的循环伏安峰。循环伏安图证明了 Hb 的 Fe(III)/Fe(II) 对的直接电子转移。₂ O ₂的检测限为6 × 10 ^-7 M (S/N = 3)。^{在 1.9 × 10 -6} ∼ 1.5 × 10 ^-4 M范围内可以观察到线性校准曲线。