Rapid fabrication of electrode for the detection of alpha fetoprotein based on MnO functionalized mesoporous carbon hollow sphere.

The concentration of alpha-fetoprotein (AFP) rises greatly in patients with liver cancer and it is a challenge to construct a sensitive AFP detection method with wide range. Therefore, an easy and label-free sensing electrochemical platform for AFP detection with wide concentration range had been designed in this work. Firstly, MnO functionalized mesoporous carbon hollow sphere (MCHS@MnO) with optimal performance was synthesized by regulating experimental conditions and characterized by scanning electron microscope (SEM), high resolution transmission electron microscopy (HRTEM), x-ray diffraction (XRD), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV), etc. Then, it was immobilized on glassy carbon electrode (MCHS@MnO/GCE) to build an immunosensor for the detection of AFP. The MCHS@MnO/GCE can catalyze decomposition of HO to generate electrochemical signal, and the signal will decrease after capturing AFP. Due to good electrocatalytic activity of MCHS@MnO to HO, the immunosensor achieved indirect detection of AFP with wide sensing range from 0.10 ng mL to 420 ng mL and a detection limit of 0.03 ng mL. Furthermore, the method had been proven to be satisfactory selectivity and reproducibility, and it was successfully applied to determine the content of AFP in human serum samples with satisfactory results. This method is expected to be used for early diagnosis and prognosis examination of liver cancer patients.