In this work, we describe a new strategy for the electrochemical determination of captopril (CA) using ferrocenemonocarboxylic
acid as a mediator and multiwall carbon nanotubes as sensors in aqueous solution at pH 7.0. The diffusion coef?cient (D), and the
kinetic parameters such as electron transfer coef?cient (a), and heterogeneous rate constant (k
), for CAwere also determined using
electrochemical approaches. Under the optimized conditions, the electrocatalytic oxidation peak current of captopril showed two
linear dynamic ranges with a detection limit of 0.3 10
6
mol L
1
h
captopril. The linear calibration range was 0.8 10
to
10
6
mol L
1
using cyclic voltammetry. Finally, this modi?ed electrode was also examined as a selective, simple and precise
w electrochemical sensor for the determination of captopril in real samples such as drug and patient human urine.
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