Electrochemical aptasensor based on 3D graphene aerogel for prostate specific antigen detection

Prostatic cancer threatens the lives and health of numerous male patients all over the world. As a single-chain glycoprotein, prostate specific antigen (PSA) can be used to perform prostate cancer screening. At present, there are still problems such as time-consuming and low sensitivity in hospital detection. At the same time, electrochemical immunosensor technology has received a lot of attention due to its benefits, including high sensitivity, good selectivity, low usage and cost, and so on. Electrocatalysts are typically used to build electrochemical immunosensors for signal amplification in the recent years to realize sensitive detection of cancer biomarkers such as PSA. In recent years, three-dimensional nanomaterials have been widely used in the study of electrocatalysts, but the study of the sensitivity for PSA detection is still very scarce. The present work reported the application of a 3D graphene aerogel(GA)/AuNPs/Nafion electrochemical platform for highly sensitive PSA quantification. The electrochemical immunosensor has been designed by immobilizing aptamers on the screenprinted electrode (SPE) surface modified by GA/AuNPs/Nafion. Scanning electron microscopy (SEM), Raman spectra, and electrochemical characterization demonstrated the successful combination of GA/AuNPs/Nafion/ SPE. Based on electrochemical impedance spectroscopy (EIS), the proposed immunosensor has demonstrated excellent electrochemical performance, exhibiting sensitive and stable responses for electrochemical detection of PSA ranging from 0.05 to 50 ngemL-1 with a limit of detection (LOD) of 0.0306 ngemL-1. This study has great potential application in PSA detection and provides a valuable reference for point-of-care testing (POCT) of prostate cancer.