Affimer-based impedimetric biosensors for fibroblast growth factor receptor 3 (FGFR3): a novel tool for detection and surveillance of recurrent bladder cancer

Fibroblast growth factor receptor 3 (FGFR3) is a transmembrane tyrosine kinase protein in the fibroblast growth factor receptor family, which plays a key role in many biological processes. Over-expression and activating mutations in FGFR3 are frequent in non-invasive bladder cancer, highlighting this protein as a potential biomarker for recurrent bladder cancer detection. Affimer reagents isolated against recombinant FGFR3 were assessed for their affinity using double-sandwich ELISA and SPR. Anti-FGFR3-14 and FGFR3-21 Affimer proteins showed strong binding to FGFR3 and were used for fabrication of impedimetric electrochemical biosensors. A decrease in impedance was observed when the sensors were exposed to increasing concentrations of FGFR3. The successful impedimetric biosensors were capable of detecting sub-pM to nM concentrations of recombinant FGFR3 protein in phosphate buffered saline as well as in synthetic urine.

Automated summary

FGFR3 is a key receptor protein with potential biomarker role in bladder cancer. Affimer reagents targeting FGFR3 showed strong binding affinity and were used for fabrication of impedimetric electrochemical biosensors. These biosensors were capable of detecting FGFR3 protein at sub-pM to nM concentrations in different solutions.