Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Biosens Bioelectron. 2014 Dec 15;62:134-9. doi: 10.1016/j.bios.2014.06.036. Epub 2014 Jun 23.
In this study, a facile non-covalent method was developed for preparing water-soluble graphene with excellent electronic conductivity. Room temperature ionic liquids (ILs) with high ionic conductivity were used for the non-covalent surface functionalization of graphene through π-π stacking interactions. Compared to other ILs used, amino acid ionic liquids (AAILs) were found to be the most effective for improving the dispersion of graphene in water phase. Electrochemical and spectroscopic results confirmed that the obtained AAIL functionalized GR can retain the excellent electronic conductivity of pristine graphene without damaging the graphene lattice. The obtained water-soluble graphene (GR-AAIL) was exemplified to fabricate an electrochemical biosensor using tyrosinase as a model enzyme, and the sensitivity (12,600 mA cm(-2) M(-1)) of GR-AAIL based biosensor was about 17 times higher than that of graphene oxide and other nanomaterial based biosensor, displaying its unprecedented high sensitivity for biosensing. The detection limit for catechol (one important environmental pollutant) reached as low as 8 nM with a response time of 3s and a linear range from 25 nM to 11,100 nM. The AAIL-GR based biosensor also demonstrated good reproducibility, repeatability, selectivity, long-term stability and high recovery for catechol detection. Amino acid ionic liquid functionalized graphene proves to be a robust and versatile electrochemical biosensing platform for fabricating biosensors with excellent performance.
在这项研究中，开发了一种简便的非共价方法来制备具有优异导电性的水溶性石墨烯。通过π-π堆积相互作用，使用具有高离子导电性的室温离子液体（ILs）对石墨烯进行非共价表面功能化。与使用的其他 IL 相比，发现氨基酸离子液体（AAIL）最有效地提高了石墨烯在水相中的分散性。电化学和光谱结果证实，所获得的 AAIL 功能化 GR 可以保留原始石墨烯的优异导电性，而不会破坏石墨烯晶格。所获得的水溶性石墨烯（GR-AAIL）被例示为使用酪氨酸酶作为模型酶来制造电化学生物传感器，并且 GR-AAIL 基生物传感器的灵敏度（12600 mA cm(-2) M(-1)）约为石墨烯氧化物和其他纳米材料基生物传感器的 17 倍，显示出其在生物传感方面前所未有的高灵敏度。儿茶酚（一种重要的环境污染物）的检测限低至 8 nM，响应时间为 3s，线性范围从 25 nM 到 11100 nM。基于 AAIL-GR 的生物传感器还表现出良好的重现性、重复性、选择性、长期稳定性和儿茶酚检测的高回收率。氨基酸离子液体功能化石墨烯被证明是一种稳健且多功能的电化学生物传感平台，可用于制造具有优异性能的生物传感器。
