Electrochemical determination of luteolin in peanut hulls using graphene and hydroxyapatite nanocomposite modified electrode

A simple and sensitive electrochemical method was developed for the determination of luteolin based on the graphene nanosheets (GNs) and hydroxyapatite (HA) nanocomposite modified glassy carbon electrode (GCE). The electrochemical behaviors of luteolin indicate that GNs and HA modified GCE (GNs/HA/GCE) can greatly enhance the electrocatalytic activity in the redox process of luteolin. It leads to a considerable improvement of the redox peak current for luteolin and allows the development of a sensitive voltammetric sensor for the determination of luteolin. A series of experimental parameters including the pH of supporting electrolyte, scanning rates, accumulation amount of GNs and HA were optimized. The results showed that the oxidative peak currents increased linearly with the concentration of luteolin in the range of 2.0 × 10−8 to 1.0 × 10−5 M, with a detection limit of 1.0 × 10−8 M (S/N = 3). The analytical performance of this sensor has been evaluated for detection of luteolin in peanut hulls as a real sample with satisfactory results.