Reduction degree and property study of graphene nanosheets prepared with different reducing agents and their applicability as a carrier of the Ru(phen) sub(3)Cl sub(2) luminescent sensor for DNA detection

Recently, graphene nanosheets (GNS) have been widely investigated and used in capacitors, catalysts, biological/chemical sensors, etc.However, the feasible applications of GNS prepared with different reducing agents as a carrier of luminescent sensors have never been systematically studied yet. Herein, a series of GNS were acquired using different reducing agents, such as hydrazine, glucose and urea. The reduction degrees and properties of the GNS samples were systematically studied by using an X-ray diffractometer, Raman spectra, IR spectra and X-ray photoelectron spectroscopy. The results indicated that the reduction degree was in the order of hydrazine > glucose > urea, demonstrating that reducing agents play an important role in the bulk fabrication of high quality graphene. Then the GNS samples were all employed as a carrier of the Ru(phen) sub(3)Cl sub(2) (tris(1,10-phenanthroline)ruthenium(II) dichloride) sensor to discriminate DNA. It is found that all the GNS samples can effectively quench the emission of the Ru(phen) sub(3)Cl sub(2) sensor. After the addition of a certain amount of DNA into the corresponding systems, the luminescence intensity was fully recovered. In comparison, the luminescence response of GNS-G prepared with glucose shows the best linear correlation to the DNA added, with a detection limit of 3.62 10 super(-9) g mL super(-1), indicating GNS-G can be employed as a good carrier of Ru(phen) sub(3)Cl sub(2) to discriminate DNA. This work will significantly advance the research of bulk fabrication of high quality graphene and the specific applications in luminescent sensors of graphene-based functional materials in the future.