Levodopa (LD), the biological precursor of catecholamines, is the most widely prescribed drug in the
treatment of Parkinson’s disease. The present work presents a proposal for the application of a carbon
paste electrode modified by ferrocene (FC) and carbon nanotubes as an electrochemical sensor for
monitoring LD. Using the electrooxidation of LD at +0.370 in phosphate buffer pH 7.0 on a ferrocene
modified carbon nanotubes paste electrode (FCMCNPE) it is possible to obtain a linear calibration
curve from 2.0×10−6 to 5.0×10−4 M and a detection limit of 1.2 μM. The method was successfully
applied to the determination of LD in urine sample without any pre-treatment.
