A New Sensor Based on Reduced Graphene Oxide/Au Nanoparticles for Glycerol Detection

Abstract The projections for the global energy demand have been one of our society’s greatest challenges, which has contributed significantly to the search for new sources of energy, among which biodiesel stands out and, consequently, the development of methods for quality assurance is essential to ensure its technological demand. In this context, a stable sensor based on graphene oxide and gold nanoparticles was developed for glycerol analysis. The electrochemically deposited gold nanoparticles presented the best results with a peak current (Ip) four times greater than the chemically produced gold nanoparticles. The combination of glassy carbon electrode with electrochemically reduced graphene and electrochemically deposited gold nanoparticles (GCE-ErGO-EAuNp) resulted in an efficient sensor to detect glycerol, promoting an Ip increase. The proposed non-enzymatic method showed a linear response in the concentration range of 1.0 x 10-3 to 1.0 x 10-2%(w/w) with a good determination coefficient (r2 = 0.9989), limits of detection and quantification at 1.2 x 10-4% and 4.0 x 10-4%(w/w), respectively, with a repeatability of (RSD% ranged from 0.36% to 2.78%), intermediate precision and recovery of (99.3% to 104.4%) and excellent stability of 700 continuous analysis cycles.