Manganese-ciprofloxacin nanocomposite-modified carbon paste electrode for potentiometric determination of moxifloxacin, norfloxacin, and levofloxacin

Abstract

This study describes a cost-effective and broad-spectrum potentiometric sensing platform for the determination of moxifloxacin, norfloxacin, and levofloxacin in pharmaceutical formulations using a manganese–ciprofloxacin nanocomposite-modified carbon paste electrode (Mn–Cip NC/CPE). The potentiometric behavior of the investigated fluoroquinolone antibiotics was evaluated using potentiometric titration under optimized experimental conditions. The proposed sensing platform exhibited satisfactory analytical performance with linear dynamic ranges of 0.004–0.400 µg/mL for the investigated analytes. The developed electrode demonstrated rapid response times (<2 s), stable potentiometric behavior within the pH range 3.0–8.0, and operational stability for approximately 10 weeks. The calculated limits of detection (LOD) were 0.003–0.004 µg/mL, while the corresponding limits of quantification (LOQ) ranged from 0.009 to 0.012 µg/mL. The fabricated Mn–Cip NC/CPE sensor was successfully applied for the determination of the investigated fluoroquinolone drugs in several commercial pharmaceutical formulations, including tablets, eye drops, and injectable preparations. The obtained analytical results showed good agreement with the official British Pharmacopoeia method, demonstrating satisfactory accuracy and precision. The proposed sensing platform combines simple fabrication, rapid potentiometric response, and acceptable analytical performance, indicating its potential applicability for routine pharmaceutical quality control analysis of fluoroquinolone antibiotics.