Fabrication of ultra-sensitive carbon paste electrode with nanocomposite CdS modification for electroanalysis of rafoxanide in dosage form and biological fluids

Abstract An anthelmintic, rafoxanide (RF), is frequently used in veterinary medicine to cure fascioliasis in cattle and sheep. A sensitive, quick, and selective detection of RF in its pharmaceutical preparation and in human urine was achieved through developing a new electrochemical sensor. The suggested method relied on the electro-oxidation of RF that used a modified carbon paste electrode in the presence of sodium dodecyl sulfate, which acts as an anionic surfactant. Voltammetric types were utilized in RF analysis, and these methods were cyclic voltammetry and differential pulse techniques. The suggested electro-analytical method’s validity is verified using the International Council on Harmonization (ICH/Q2) rules. The calibration curve for RF quantification was done in the concentration range from 2.9 × 10−6 to 3.1 × 10−4 M at cadmium sulfide modified carbon paste electrode. The limit of detection and the limit of quantification LOQ were found to be 6.7 × 10−7 M and 2.01 × 10−6 M, respectively. This study could be applied to the examined drug in QC-laboratory units, and also RF could be assayed in its pharmacokinetic studies. Graphical abstract