Preparation Of Graphene Composites And Its Application In Biological Detection

Graphene, as a new two-dimensional nanomaterial, has enjoyed significant recent attention. The ideal monolayer graphene has extended honeycomb structure lattice. It’s a new member of carbon, besides with OD fullerenes, ID carbon nanotubes,3D diamond and so on. Geim and co-workers isolated single-layer samples from graphite in2004for the first time. Graphene has many excellent physical and chemical properties. In recent years, graphene mainly applied in solar cell, nanoelectronic devices, energy storage, molecule sensor and biological medicine, etc. We are mainly focus on the application of graphene used in biological detection.In our study, first we prepare graphene oxide, then reduce grapheme oxide by starch in water dissolving phase, microwave as reduction condition, aim to get Reduced Graphene Oxide (RGO) with vacancys on the planar for facilitate the combination of composite materials. Starch as reducing agent is green, source selection simple, and under high temperature can get glucose, and glucose can be very good reduction graphene. The results of reduction oxidation are detected by UV-vis, and the morphology and structure of graphene are charactered by TEM, SEM, XRD and FT-IR. XPS analysis results show the graphene oxide with large amounts of oxygen such as carbonyl, hydroxyl groups, carboxyl, and epoxy. Due to these polar groups, the graphene oxide has the very good hydrophilic. According to the results of, the carboxyl was reduced. And part of the starch can compound to graphene surfaces, which might provide the nanoparticles composite site.We also use in-situ composite and physical adsorption synthesis silver nanoparticles composite on graphene. The result shows that through the microwave and starch of reduction, the Ag NP grow on RGO (RGO/starch-Ag) successfully, and the average size of particle is34nm. So RGO/starch-Ag has Raman enhancement effect and antibacterium. The results indicate that the Ag NP@RGO antibacterial activity against Pseudomonas aeruginasa and the minimum inhibitory concentration (MIC) is0.5%. Compare with in-situ composite, the Ag NP on physical adsorption S-RGO/starch-Ag is very less. The Raman enhancement effect is very poor. Antibacterial activities of S-Ag NP@RGO is approximate no effect, because of the less composited nanoparticles of this type.