Nonenzymatic Glucose Biosensor Based on NiNPs/Nafion/Graphene Film for Direct Glucose Determination in Human Serum

This study describes a type of novel nickel nanoparticles (NiNPs) decorated on Nafion-graphene composite film by using the electrochemical deposition method. It was used to fabricate electrochemical biosensors for sensitive nonenzymatic glucose detection. Compared with the Nafion–graphene film and NiNPs-modified glassy carbon electrode (NiNPs-GCE), the NiNPs/Nafion/graphene/GCE showed the best electrocatalytic activity towards glucose oxidation in alkaline medium. The NiNPs/Nafion/graphene/GCE at an applied potential of + 0.55 V in a linear range of 1–200 μ M presented a high sensitivity of 3437.25 μ A ⋅ mM − 1 cm − 2 with coefficient of correlation R 2 = 0 . 9 9 9 ; and in a linear range of 200–10 800 μ M it performed the best sensitivity of 2848.6 μ A ⋅ mM − 1 cm − 2 with coefficient of correlation R 2 = 0 . 9 9 5 towards glucose oxidation. For a concentration up to 200 μ M, a linear range was obtained with a limit of detection of 0.6 μ M (signal to noise = 3) and as much as 10 800 μ M with a limit of detection of 0.82 μ M (signal to noise = 3). The time of responses was about 1–1.5 s with the addition of 0.1–1 mM glucose. In addition, NiNPs/Nafion/graphene/GCE also has a high anti-interference ability toward common oxidative interfering species, such as uric acid, ascorbic acid and dopamine. More importantly, NiNPs/Nafion/graphene/GCE was successfully used for the determination of glucose concentration in human serum samples in comparison with a local hospital. The NiNPs/Nafion/graphene/GCE exhibited high sensitivity, low working potential, good stability, excellent electrical properties, enhanced selectivity and fast amperometric responses to glucose oxidation. Thus, as a nonenzymatic sensor, it is promising for future glucose determination development.