An enhancement of luminol chemiluminescence by cobalt hydroxide decorated porous graphene and its application in glucose analysis

Here, it was shown that a cobalt hydroxide/porous-graphene nanocomposite (PG/Co(OH)2) has great catalytic capability toward luminol as a chemiluminescence active substrate. We made use of PG/Co(OH)2 for developing a super-sensitive quantitative analytical tool for glucose detection. After optimizing the effective factors, the relative chemiluminescence intensity was found to linearly change with H2O2 concentration from 5.0 × 10-11 to 1.0 × 10-6 mol L-1 (R2 = 0.99023) and a detection limit as low as 8.0 × 10-12 mol L-1 (S/N = 3). The association between the CL signal intensity and H2O2 concentration was obtained. Based on the production of H2O2 by glucose oxidase from glucose, the detection of glucose was performed and it could be linearly detected in the range from 3.0 × 10-9 to 4.0 × 10-5 mol L-1 (R2 = 0.99106) with a detection limit of 6.4 × 10-10 mol L-1. This method was also implemented for non-invasive determination of glucose in tears and saliva, which is important for diabetic patients with frequent/continuous glucose monitoring requirements, and satisfactory results were obtained.