An Au-Pd/reduced graphene oxide composite was employed as a novel electrode material for the sensitive and
simultaneous determination of ascorbic acid, acetaminophen and tyrosine. The electrochemical response characteristics
of the modified electrode toward the analytes were investigated by differential pulse voltammetry and
cyclic voltammetry. The responses of the electrochemical sensor for the target analytes were found to be improved
significantly in comparison with those obtained using a conventional carbon paste electrode (CPE) and
reduced graphene oxide/CPE. The experimental conditions for simultaneous determination of these species
have been established. Ternary mixtures of analytes can be determined in the ranges of 0.03–9.50 μM. Under optimal
conditions, the limits of detection were 15.7, 7.6 and 11.1 nM for ascorbic acid, acetaminophen, and tyrosine,
respectively. The method was applied successfully to determine the analytes in urine, serum and
pharmaceutical samples simultaneously.