Ethylenediamine grafted carbon nanotube aerogels modified screen-printed electrode for simultaneous electrochemical immunoassay of multiple tumor markers

•Hybrid carbon aerogels were synthesized and introduced for immunosensor application.•The sandwich configuration immunosensor was based on the screen-printed technology.•Redox mediators (dyes) have been used as labels.•The improved immunosensor was employed for individual and simultaneous electrochemical detection of AFP and CEA.•The developed EC sensor provided a sufficient linear range of 0.005–1.0 ng/mL for AFP and CEA.