Hierarchical nickel hydroxide nanosheets grown on hollow nitrogen doped carbon nanoboxes as a high-performance surface substrate for alpha-fetoprotein cancer biomarkers electrochemical aptasensing.

During recent decades, we have witnessed a great improvement in the performance of aptamer-based sensors, specifically when aptamers are combined with new nanomaterials; as a platform for biosensors. The design of hollow carbon-based materials has also received a lot of attention due to its excellent properties in various applications. Herein, we aim at designing hierarchical porous Ni(OH) nanosheets on hollow N-doped carbon nanoboxes Ni(OH)@N-C n-box). In this sense, we obtained the hollow N-C n-box skeletons from the FeO nanocubes template. The development of label-free electrochemical aptasensor was carried out using the covalently immobilizing NH-functionalized aptamer on Ni(OH)@N-C n-box as an efficient substrate. The Ni(OH)@N-C n-box was characterized using scanning fourier transform infrared spectroscopy (FTIR), X-ray Diffraction (XRD), Brunauer, Emmett and Teller (BET), transmission electron microscopes (TEM) and electron microscopy (FESEM). The electrochemical evaluations clarified the fact that a linear relationship exists between the alpha-fetoprotein (AFP) contents and the charge transfer resistance (R) (from 1 fg mL to 100 ng mL) with a low detection limit of 0.3 fg mL. Moreover, regarding the aptasensor, the superior detection recoveries were experienced in real biological samples, illustrating its great detection performance and practical feasibility. Considering the aptasensor application, these studies showed that Ni(OH)@N-C n-box possesses different enhanced electrochemical features, making it appropriate as an electrode material for aptasensor application.