Key Laboratory of Mesoscopic Chemistry (Ministry of Education), State Key Laboratory of Coordination Chemistry, and School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210093, PR China.
Biosens Bioelectron. 2014 Jan 15;51:343-8. doi: 10.1016/j.bios.2013.08.007. Epub 2013 Aug 15.
Biofunctionalized graphene-gold nanoparticle (AuNP) hybrids were prepared using a facile approach of in situ growth, with homogeneous distribution of AuNPs on the graphene nanosheets. Hemoglobin (Hb) was immobilized on the graphene-AuNP composites to fabricate biosensors for determination of nitrite (NO2(-)). A pair of well-defined redox peaks was observed for Hb immobilized on the graphene-AuNP hybrids with a formal potential (E(0')) of -0.314 V in 0.1 M phosphate buffered saline (0.15 M NaCl, pH 7.0). The novel biosensors exhibited many advantages, such as wide linear response range (from 0.05 to 1000 µM, R(2)=0.997), low detection limit (0.01 µM, a signal to noise ratio of 3), high sensitivity (0.15 μA μM(-1) cm(-2)), and excellent selectivity. These constructed biosensors were further used for determination of nitrite in pickled radish. The results obtained were in good agreement with those using spectrophotometry based on the National Food Safety Standard (GB 5009.33-2010), which indicates that these novel and sensitive biosensors have promising application for determination of nitrite in food.
采用简便的原位生长方法制备了生物功能化的石墨烯-金纳米粒子（AuNP）杂化物，AuNP 在石墨烯纳米片上均匀分布。血红蛋白（Hb）固定在石墨烯-AuNP 复合材料上，用于制备用于测定亚硝酸盐（NO2(-)）的生物传感器。在 0.1 M 磷酸盐缓冲盐水（0.15 M NaCl，pH 7.0）中，固定在石墨烯-AuNP 杂化物上的 Hb 表现出一对定义良好的氧化还原峰，其形式电位（E(0')）为-0.314 V。新型生物传感器具有许多优点，例如宽线性响应范围（从 0.05 到 1000 μM，R(2)=0.997），低检测限（0.01 μM，信噪比为 3），高灵敏度（0.15 μA μM(-1) cm(-2)）和出色的选择性。这些构建的生物传感器进一步用于测定泡菜中的亚硝酸盐。得到的结果与基于国家标准食品安全标准（GB 5009.33-2010）的分光光度法得到的结果吻合良好，这表明这些新型灵敏的生物传感器在食品中亚硝酸盐的测定中有广阔的应用前景。
