Nitrogen-Doped Graphene Supported α-Co(OH)₂ for Sensitive Determination of Adrenaline

Abstract

For a happy and healthy life, there should have a balance of flight-to-flight hormones, i.e, adrenaline (AD). The necessity of determination of AD is inevitable for the diagnosis of associated diseases with it. For this purpose, N-doped graphene supported α-Co(OH)2 (denoted as NrGO/α-Co(OH)2) was synthesized via a hydrothermal process, where α-Co(OH)2 acted as an active site and NrGO provided a better defective surface for immobilized α-Co(OH)2 nanoparticles. The as-prepared nanocomposite altered the electronic configuration due to its defective nature, which played an important role to increase the stability, surface area and electron transfer capability. As a result, NrGO/α-Co(OH)2 demonstrated remarkable analytical performances toward AD with a lower limit of detection (14.7nM), wide linear range (0.5-800µM), and good sensitivity (115.983 µA mM−1 cm-2). The CA response time was obtained as 2.2 s. The proposed sensor showed precious selectivity during AD detection in presence of coexisting biomolecules such as DA, AA, UA, TY, 5-HT, and NE, and 50-fold excess of common ions such as Na+, K+, Ca2+, Mn2+, Fe2+, CO32-, and SO42-. Furthermore, it also provided long-term stability, good reproducibility and repeatability with practical feasibility in the urine sample. Importantly, the effect of pH was studied in detail on AD oxidation.