Highly sensitive electrochemical detection of carcinoembryonic antigen by silver nanoparticles/carboxylated single-walled carbon nanotubes embedded in mesoporous carbon foam

Carbon-based mesoporous foam nanostructures have gained significant attention because of features like high specific surface area, stability, abundant porosity, good conductivity, and excellent biocompatibility. Highly mesoporous carbon foam (MCF) was properly synthesized via the low-cost, template-free, simplistic Pechini method. Functional nanomaterials can be incorporated into the surface of MCFs to design functionalized MCFs for a broader range of applications. This opens up new horizons for designing MCFs that can be used in various fields. This study aims to introduce a new type of MCF decorated with carboxylated single-wall carbon nanotubes (CSWCNTs) and silver nanoparticles (AgNPs). An amine-functionalized aptamer was immobilized on the modified glassy carbon electrode (GCE) by covalent bonds and electrostatic interactions to determine carcinoembryonic antigen (CEA) in serum samples. The designed aptasensor best operated at 0.05 V (vs. Ag/AgCl) and showed a wide linear range from 1 × 10 −6 to 20 ng mL −1 , high sensitivity (27.96 μA mL ng −1 cm −2 ), low limit of detection (0.30 fg mL −1 ), high bioaffinity, superior selectivity, and good reproducibility. As the results indicated, the AgNPs/CSWCNT/MCF nanocomposite–based homogenous aptasensor platform has great potential for the low-cost clinical detection of other tumor markers in complex biological environments.