A biosensor platform based on amine functionalized conjugated benzenediamine‐benzodithiophene polymer for testosterone analysis

A novel benzenediamine‐benzodithiophene polymer is synthesized for use in biosensor fabrication for the detection of testosterone. The sensory platform is constructed via drop coating on a screen‐printed carbon electrode, using poly(benzenediamine‐Bis[(2‐ethylhexyl)oxy]benzodithiophene) (pBDBT) as the polymer layer. Testosterone antibodies are immobilized on the polymer‐coated electrode surface via glutaraldehyde, which binds to the surface through the amino functional groups on the polymer backbone. The changes in the surface features due to testosterone binding are investigated via electrochemical techniques such as differential pulse voltammetry, cyclic voltammetry, and electrochemical impedance spectrometry as well as contact angle measurements. Surface morphology of the modified electrodes is characterized by atomic force microscopy. The linear range and limit of detection of the sensor are calculated. Impact of possible interfering compounds is investigated. Furthermore, the sensory platform is utilized for testosterone analysis in synthetic biological fluids. A novel benzenediamine‐benzodithiophene polymer bearing amino groups is designed and synthesized to facilitate binding of biorecognition elements. Biosensor is custom designed to be employed in the detection of testosterone in different matrices. The step‐by‐step surface modifications are monitored by DPV, CV, EIS, AFM, and contact angle measurements. Impact of possible interfering compounds in synthetic biological fluids is investigated.