A sensitive and stable electrochemical immunosensor for glycocholic acid in serum detection based on MoS2 and MWCNTs composites

Glycocholic acid detection (cholyglycine, CG) is desirable as a liver disease marker. In this study, a sensitive and stable immunosensor for rapid detection of CG was constructed. This immunosensor was fabricated by immobilizing CG antibodies on MoS₂ composites containing gold nanoparticles (AuNPs) and molybdenum disulfide (MoS₂) with multi-walled carbon nanotubes (MWCNTs) as an electrical signaling carrier. The immunosensor had outstanding sensitivity and stability. It showed good analytical performance in human serum, with a detection limit of 1 ng/mL and a linear range of 1–80 ng/mL. The detection results of the CG immunosensor are consistent with the latex-enhanced immunoturbidimetry. The tests of the detection capabilities for actual samples verified that the prepared immunosensors had excellent selectivity, high sensitivity, and sufficient reproducibility, and satisfactory results were obtained. This method shows great potential for the detection of CG in serum.