Highly efficient electrochemical biosensing platform in breast cancer detection based on MOF-COF@Au core-shell like nanostructure

Nowadays, rapid and facile diagnosis of cancer using user friendly processes has attracted much attention. In this regard, an electrochemical (EC) biosensor with high sensitivity was fabricated by merging MIL156 MOF@COF nanocomposite with Au nanoparticles for the detection of CA15-3. Herein, metal clusters of MIL-156 as a Metal organic frameworks (MOF) were coated by a crystalline covalent organic frameworks (COF) through covalent bonding and created core-shell-like structures. The active part of the working electrode was modified in two consecutive steps. First, MIL-156 MOF@COF and then Au nanoparticles were electrodeposited on the glassy carbon electrode (GCE). The porosity of nanocomposite has significantly increased the surface area and improved the conductivity. Au nanoparticles also form an acceptable substrate for bonding antibodies due to their high affinity with amino groups. In addition, Au nanoparticles amplify the EC signal of the biosensor with their undeniable conductivity. Nanocomposite was characterized with XRD, SEM, and EDAX techniques. To investigate the proposed biosensor, differential pulse voltammetry (DPV) was used as an analytical technique. The CA15-3 calibration provided a linear range between concentrations of 30 and 100 nU/mL, thus expressing the powerful diagnostic potential of the designed biosensor. Furthermore, the suggested biosensor has been used in serum samples and discriminate breast cancer sufferers from healthy individuals with high confidence levels.