Senescence-associated β-galactosidase detection in human oral cancer samples using bimetallic (Fe, Cu)-MOF-919 impedimetric immunosensor

• Senescence associated β-gal sensing. • Bimetallic (Fe,Cu)MOF/ SPCE as working electrodes. • Unprecedented biosensor for human β-gal. Clinical diagnosis of diseases like cancer, requires rapid and ultrasensitive screening methods. β-galactosidase (β-gal) is a glycoside hydrolase enzyme, that is upregulated in senescent cells and primary ovarian cancer cells. It is considered a significant biomarker for cellular senescence and primary ovarian cancers. The current study demonstrates the designing of a bimetallic metal-organic framework, (Fe, Cu)-MOF-919, as an ultrasensitive electrochemical immunosensor for investigating ꞵ-galactosidase (β-gal) enzyme on screen-printed carbon electrodes (SPCE) using electrochemical impedance spectroscopy (EIS) in human oral cancer plasma samples. The sensor exhibited a linear response in a wide concentration of β-gal ranging from 10 fg/mL to 1 ng/mL with a limit of detection (LOD) of 4.79 fg/mL and a limit of quantification (LOQ) of 14.53 fg/mL. Furthermore, the sensor confirmed outstanding selectivity and sensitivity against biologically significant interfering molecules. Analyses of β-gal in human oral cancer samples also demonstrated the potential of β-gal for clinical diagnosis. The sensing approach holds substantial clinical relevance by being a promising option for designing latent biosensors.