Design of point-of-care electrochemical sensor for therapeutic drug monitoring of ofloxacin in biological fluids

Abstract A disposable screen-printed sensor has been crafted specifically for therapeutic drug monitoring purposes, particularly for detecting ofloxacin in biological fluids. To enhance selectivity toward ofloxacin, a supramolecular calix [6] arene serves as the ionophore of choice. The sensor incorporates a graphene nanocomposite as an ion-to-electron transducer layer, which not only boosts potential stability but also mitigates potential drift. The developed ofloxacin sensor underwent rigorous characterization following IUPAC guidelines. The linearity range spans from 1 × 10–6 to 1 × 10–2 M, with a measured slope of 59.0 mV/decade. Impressively, it boasts a percentage recovery of 100.18 ± 1.60 and a low detection limit (LOD) of 6 × 10–7 M. Stability assessments indicate reliable performance over an extended period of 8 weeks. The versatility of this sensor extends to various applications, including the determination of ofloxacin in pharmaceutical formulations, bulk powder, and biological fluids. Notably, it has demonstrated efficacy post-bioanalysis validation, adhering to Food and Drug Administration regulations. This advancement holds promise for personalized therapeutic drug monitoring in clinical pharmacy studies and quality control laboratories, thereby optimizing patient care at the point-of-care. Graphical abstract