Simultaneous Detection of Nalbuphine and Diclofenac as Important Analgesic Drugs in Biological and Pharmaceutical Samples Using a Pt:Co Nanostructure-Based Electrochemical Sensor

Nalbuphine (NB) and diclofenac (DF) are two important drugs for the relief of moderate to severe pain and determination of them are very important due to complications related to their overdose. A promising nanostructure modified electrode was fabricated by distributing Pt:Co nanoalloy (Pt:Co/NL) into carbon paste matrix in the presence of 1-methyl-3-butylimidazolium bromide (1M3BIBr) as a conductive binder. Energy-dispersive X-ray spectroscopy analysis (EDAX), transmission electron microscopy (TEM) and X-ray powder diffraction (XRD) were employed to confirm the synthesis of Pt:Co/NL by polyol method. The proposed sensor was applied to the simultaneous determination of nalbuphine (NB) and diclofenac (DF) in pH 7.0 phosphate buffer solution for the first time. The calibration curves for NB, and DF were obtained in the ranges of 0.05 to 1290 μM and 0.1 to 900 μM, respectively. The detection limits (3σ) were 9 nM and 50 nM for NB and DF, respectively. The interference study shows that the carbon paste electrode modified with Pt:Co/NL and 1M3BIBr (Pt:Co/NL/1M3BIBr/CPE) exhibits excellent selectivity for determination NB and DF in the presence of other biological specie. The 1M3BIBr was applied to ampule and tablet samples and excellent results were obtained.