Ni-Fe PBA hollow nanocubes as efficient electrode materials for highly sensitive detection of guanine and hydrogen peroxide in human whole saliva

Abstract

A sensor for the determination of guanine (G) and hydrogen peroxide (H₂O₂) is developed based on Ni-Fe Prussian blue analogues hollow nanocubes (Ni-Fe PBA HNCs) for the first time. As a remarkable redox probe towards G and H₂O₂ oxidation, Ni-Fe PBA HNCs exhibit a series of predominant sensing performances as follows: lower limit of detection, broader linear range and higher selectivity due to the homogeneous hollow structure, high specific surface and the enhanced electron transfer ability of Ni-Fe PBA HNCs. As a G sensor, it exhibits a wide linear range (0.05-4.0 mM) and a low detection limit of 0.0104 μM (S/N = 3). As a H₂O₂ sensor, the Ni-Fe PBA HNCs show superior sensing performances with a low detection limit of 0.291 μM (S/N = 3) and a wide detection range of 0.1-20 mM. By cause of these advantages, the real-time detection of G and H₂O₂ in human saliva are triumphantly accomplishment, indicating the applicability of Ni-Fe PBA HNCs.

Keywords: Guanine; H(2)O(2); Hollow; Ni-Fe; Prussian blue analogue; Sensor.