A Highly Sensitive Electrochemical Sensor Based on B, N Co-Doped Porous Carbon/Cobalt Composite for Trace Determination of Bosutinib in Biological and Pharmaceutical Samples

Abstract A novel electrochemical sensor was constructed using a boron–nitrogen co-doped porous carbon composite containing cobalt species (C2BN/Co@PCS) for the sensitive determination of bosutinib (BOS). The nanocomposite was synthesized utilizing phenylboronic acid, an inorganic salt mixture, and ZIF-12, yielding a hierarchical porous structure with high surface area, abundant active sites, and enhanced electrical conductivity. The structural properties were confirmed by XRD, Raman, XPS, SEM, TEM, and nitrogen adsorption analyses. The electrochemical behavior of the C2BN/Co@PCS/GCE was investigated using cyclic voltammetry and electrochemical impedance spectroscopy. The modified electrode exhibited a significant increase in electroactive surface area (0.191 cm² vs 0.094 cm²), enhanced redox response, and reduced charge-transfer resistance (1600 Ω vs 3900 Ω), indicating improved electron-transfer kinetics. Differential pulse voltammetry was used for BOS quantification, yielding a linear range of 0.1–4.0 µM and a detection limit of 0.013 µM. The proposed sensor also demonstrated excellent selectivity, as evaluated against a range of potentially interfering species including inorganic ions and biologically relevant electroactive molecules. Furthermore, the sensor exhibited good repeatability and reproducibility. Practical applicability was confirmed in tablet, serum, and urine samples with recoveries of 96.99–103.7%. Overall, the developed sensor offers a rapid, sensitive, and reliable platform for BOS detection in complex matrices.