Next-generation BZ-TFP-COF/MWCNTs electrochemical interface for real-time dual monitoring of dopamine and paracetamol in blood

Real-time and simultaneous detection of dopamine (DA) and paracetamol (PA) is critical for understanding neurochemical dynamics and drug metabolism with important implications in the early diagnosis and clinical treatment. Co-detection in biological fluids, however, is problematic due to interfering overlapping redox potentials as well as endogenous biomolecule interference. (a) Synthesis Approach In this research work, a new generation electrochemical sensor was fabricated by utilizing a synergistic hybrid of benzidine-1,3,5-triformylphloroglucinol covalent organic framework (BZ-TFP-COF) and multi-walled carbon nanotubes (MWCNTs). The BZ-TFP-COF was prepared through a Schiff-base condensation reaction and further combined with MWCNTs to create a nanocomposite ink for the modification of electrodes. (b) Material Properties The BZ-TFP-COF component is characterized by high surface area and rich functional groups for efficient immobilization of the analyte, whereas MWCNTs possess superior electrical conductivity and facilitate rapid electron transfer. The resulting hybrid interface proves enhanced electrocatalytic activity, sensitivity, and strong anti-interference potential. (c) Sensor Application The sensor showed broad linear ranges for both DA and PA (0.05–500 µM) with low detection limits of 0.05 µM and 0.06 µM, respectively. Anti-interference investigations verified >50-fold selectivity against general bioactive interferents. The disposable sensor showed superior reproducibility and was successfully used in spiked human serum samples with recoveries > 97 %, thereby allowing reliable and real-time electrochemical detection of DA and PA in biological fluids.