A highly sensitive chemiluminescent probe for detection of glutathione based on gold nanostar@redecued graphene oxide composite

Gold nanostars (GNSs) are particularly interesting class of plasmonic particles. They consist a near-spherical core and multiple branches with sharp tips, which create lots of ‘‘hotspots’’ and enhance the local electromagnetic fields strongly [1,2]. Here we describe for the first time, the application of GNS@rGO in CL and demonstrate their remarkable enhancing effect on luminol-IO4– reaction. This enhancement was supposed to result from the unique catalytic action of GNS@rGO, which leads to the acceleration of reactive oxygen species generation. It was also found that a remarkable increase in the CL intensity of GNS@rGO-luminol-NaIO4 system occurs in the presence of glutathione (GSH). Based on this observation, a simple and highly sensitive CL probe was developed for detection of GSH. With the optimum conditions chosen, the calibration curve exhibits linear range from 1.0 nM to 1.0 μM for GSH with a detection limit of 0.2 nM. The developed nano sensor was applied to the detection of GSH in human plasma samples with satisfactory results.