Co-MOF and c-MWCNT Nanocomposite–Based Impedimetric Immunosensor for Sensing of Human Serum Albumin

Cobalt metal–organic framework (Co-MOF), also called zeolite imidazole framework (ZIF-67), a subclass of MOF, is a burgeoning class of crystalline materials that features high porosity, large surface areas, remarkable stability, and flexibility. A coordination bond between an organic linker and a redox-active cobalt metal center forms ZIF-67 MOF, which has a unique architecture resembling zeolites. However, ZIF-67’s limited conductivity impedes its application for electrochemical sensing. Considering this, we designed Co-MOF-carboxylated multiwalled carbon nanotubes (c-MWCNTs) nanohybrid, which was further functionalized with an anti-ALB antibody to enable the selective electrochemical evaluation of albumin (ALB), a clinically proven kidney biomarker. ALB, the most prevalent protein secreted by hepatocytic cells, performs a number of essential bodily functions; however, a deviation from a normal level is prognostic of kidney failure and other illnesses. Several physical and electrochemical methods were utilized to thoroughly characterize the developed immunosensing device. Following that, electrochemical impedance spectroscopy (EIS) was employed to evaluate its efficacy, and the linearity and detection limit were estimated as 0.1–60 mg/mL and 0.024 mg/mL, respectively. These remarkable outcomes are the result of c-MWCNT and Co-MOF synergistic effects, and they present a cutting-edge approach for point-of-care ALB detection using composite materials based on MOFs.