Rapid Detection of Nitrite in Food Using the Electrode Modified by Hemoglobin/Gold Nanoparticle-reduced Graphene Oxide Composite
Article
Figures
Metrics
Preview PDF
Reference
Related
Cited by
Materials
Abstract:
Nitrite (NO2-) was detected by a glassy carbon electrode (GCE) modified by hemoglobin (Hb) with gold nanoparticle-reduced graphene oxide (AuNPs-rGO) composite. The qualitative and quantitative detection of nitrite were conducted using the signal of a direct electron transfer generated from methemoglobin and NO3- that were produced by the redox reaction between hemoglobin and nitrite. The GCE surface was modified by AuNPs-rGO composites to produce AuNPs-rGO/GCE, which was modified by Hb after drying to form an Hb/AuNPs-rGO/GCE biosensor. After the modified electrode was coated with 80 μL of 0.5% Nafion to form a Nafion film, the Nafion/Hb/AuNPs-rGO/GCE biosensor was finally obtained. The results showed that the biosensor had good selectivity and sensitivity when cyclic voltammetry method was used to detect nitrites, with a relative wide linear range from 0.5 to 100 μM. The relationship between peak current and the nitrite concentration could be described by the linear equation of IP = 0.0369C(NO2-) + 0.2245 (R = 0.9918), and the limit of detection was 0.1 μM. This method is simple, rapid, sensitive and can be used for nitrite detection in food and environmental samples.
