Background: Electroanalytical methods are very functional to detect drugs in
pharmaceuticals (tablets, syrups, suppositories, creams, and ointments) and biological samples.
Objective: This study is aimed to make selective, sensitive, simple, fast, and low cost
electrochemical analysis of expectorant drug guaifenesin in pharmaceuticals and serum samples.
Methods: Differential pulse adsorptive stripping voltammetric method for determination of
guaifenesin on a poly(acridine orange) modified glassy carbon electrode has been developed.
Glassy carbon electrode was modified with electropolymerization of the acridine orange monomer
for the sensitive determination of guaifenesin. Guaifenesin provided highly reproducible and welldefined
irreversible oxidation peaks at +1.125 V and +1.128 V (vs. Ag/AgCl) in the selected
supporting electrolyte and human serum samples, respectively.
Results: Under optimized conditions, linear response of peak current on the concentration of
guaifenesin has been obtained in the ranges of 2.00×10-7 to 1.00×10-4 M in Britton Robinson buffer
solution at pH 7.0 and 4.00×10-7 to 1.00×10-4 M in serum samples. The precision of the method
was detected by intraday and inter-day repeatability studies in the supporting electrolyte and serum
Conclusion: The analytical applicability of the proposed method exhibited satisfying
determination results for guaifenesin from pharmaceutical dosage forms (syrup) and human serum
samples without any pre-separation procedures.