Direct decoration of carbon nanohorns with binary nickel-cobalt sulfide nanosheets towards non-enzymatic glucose sensing in human fluids

•A green, simple, two step, in-situ synthesis is suggested for direct growth of NiCo-S/CNH/GCE (and GSPE).•Using prepared NiCo-S/CNH/GCE as a non-enzymatic sensing platform based on non-precious metals for glucose measurement.•High sensitivity, fast response, excellent repeatability and reproducibility, remarkable selectivity, and long-term stability were also resulted.•The sensor was successfully applied for determining glucose level in the human fluids’ samples without any sample pre-treatment.•The proposed electro-catalyst was fabricated on commercial screen-printed electrode and examined for clinical samples. A highly controllable, green, and rapid strategy is demonstrated for fabricating of highly sensitive non-enzymatic glucose sensing platforms. Carbon nanohorns (CNHs) were decorated onto the screen-printed electrodes. Binary nickel-cobalt sulfide (NiCo-S) nanosheets (NSs) were then deposited on CNH-casted electrodes by a facile and scalable method. Following detailed structural characterization and the electrocatalytic activity of the fabricated NiCo-S/CNH electrodes towards electro-oxidation of glucose was examined in detail. The proposed electrodes operated within two distinct linear dynamic ranges of 0.001- 0.330 mM and 0.330 - 4.53 mM with sensitivities of 1842 µA.mM−1.cm−2 and 854 µA.mM−1.cm−2, respectively. Analytical sensitivity of 467 µA.mM−1.cm−2, within the linear dynamic range of 0.5 ∼ 6 mM, was obtained for the static chronoamperometric measurements. The proposed sensor showed outstanding selectivity against isostructures and co-existing interferences, long-term stability, fast response (1.7 s), excellent poisoning resistance against chloride ions, good repeatability, and high reproducibility. The structural and electrochemical properties of the NiCo-S/CNHs were also compared to its mono-metallic counterparts. Finally, to demonstrate the capability of the fabricated electrodes for glucose measurements in physiological specimens, the glucose level was successfully measured in human blood serum, urine, and saliva samples, without any sample pre-treatment.