A novel and ultrasensitive sandwich-type electrochemical immunosensor based on delaminated MXene@AuNPs as signal amplification for prostate specific antigen (PSA) detection and immunosensor validation.

In this study, an ultra-sensitive electrochemical immunosensor for PSA detection was designed. Firstly, gold nanoparticles (AuNPs)/p-aminothiophenol (ATP) functionalized graphene oxide (GO) composite (AuNPs-ATPGO) was constructed and modified to glassy carbon electrode (AuNPs-ATPGO/GCE). AuNPs-ATPGO/GCE was utilized as immunosensor platform to increase the amount of PSA antibody1 (Ab 1). After that, self-assembled delaminated MXene-gold nanoparticles (d-Ti 3 C 2 T X MXene@AuNPs) was used to label PSA seconder antibody2 (Ab 2) as signal amplification. The prepared AuNPs-ATPGO, d-Ti 3 C 2 T X MXene@AuNPs and electrochemical immunosensor was charecterized by electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), scanning electron microscope (SEM), x-ray diffraction (XRD) method, x-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), fourier transform infrared spectroscopy (FTIR). The linearity range and detection limit (LOD) were obtained as 0.01–1.0 pg mL-1 and 3.0 fg mL-1, respectively. Image 1 • Ultra-sensitive sandwich type electrochemical immunosensor is developed for prostate recognition. • The prepared immunosensor is characterized by several methods. • The prepared immunosensor shows high stability, repeatability, reproducibility and reusability. • The prepared immunosensor is preferred in comparison with the other analytical methods. [ABSTRACT FROM AUTHOR]