▎ 摘　　要

Microfluidic electrochemical sensors are emerging as favorable platforms for rapid and precise detection of disease markers relying on their superiority of miniaturization, low electrolyte consumption, high precision and integration. Herein, an efficient and facile integrated microfluidic sensor with three-dimensional graphene fiber film/chitosan-gold nanoparticles (3D GF/CS-Au NPs) micro-nano composites as sensing interface was developed for the analysis of prostate specific antigen (PSA). The GF with 3D network structures modified by large amounts of CS-Au nanoparticles could facilitate the enhancement of electrochemical signals. The electrodes and micro-channel were simply assembled and encapsulated by bolts, which made the microfluidic chip had excellent portability and operability. On the basis of this new microfluidic device and the 3D GF/CS-Au NPs composites, a sensitive determination of PSA could be realized with a low detection limit of 0.51 pg/mL and a wide response range from 0.001 -200 ng/mL. Moreover, the proposed biosensor was further used to detect analytes in human blood samples, showing the satisfactory results. This novel microfluidic electrochemical immunosensor demonstrated superior performance for PSA detection, holding potential application in clinical diagnosis and personalized healthcare.