Positively charged carbon nanoparticulate/sodium dodecyl sulphate bilayer electrode for extraction and voltammetric determination of ciprofloxacin in real samples

Abstract

In this study, ciprofloxacin, a second-generation fluoroquinolone antibiotic, has been analyzed in human serum and a pharmaceutical preparation by a modified carbon paste electrode. The modified electrode was prepared using a layer-by-layer method with functionalized carbon nanoparticles and sodium dodecyl sulphate. Carbon nanoparticles (Emperor 2000™) were functionalized with ethylene diamine using a chemical method. The functionalized carbon nanoparticles were studied with scanning electron microscopy and FTIR spectroscopy. The modified electrode was characterized with electrochemical impedance spectroscopy and cyclic voltammetry. The ability of modified electrode to adsorb ciprofloxacin was investigated. The extraction parameters such as time, pH and agitation rate were optimized. In optimum conditions, ciprofloxacin was adsorbed at the surface of electrode and its electro-oxidation was studied. Differential pulse voltammetry was applied for quantitative determinations. Two linear ranges 5.0 × 10⁻⁷ to 1.0 × 10⁻⁵ mol L⁻¹ and 3.0 × 10⁻⁸ to 5.0 × 10⁻⁷ mol L⁻¹ with a limit of detection of 5.0 × 10⁻⁹ mol L⁻¹ were obtained. The prepared electrode exhibited the successful ability for the determination of ciprofloxacin in real samples such as human serum and commercial tablets with recoveries 99.85% and 101.5%, respectively.