This paper has presented a novel strategy to carry out direct and sensitive determination of ampyra in complex matrices based on the L-cysteine/Cu modified gold electrode. This novel structure was characterized by different techniques including atomic force microscopy (AFM) and Fourier-transform infrared (FT-IR) spectrometry. Ampyra determination by conventional electrochemical methods is not possible, because of high potential of its redox. Therefore, electrochemical impedance spectroscopy of ferricyanide was used as a marker to probe the interface and as a redox probe to determine ampyra. The fabricated electrochemical sensor showed good electrochemical response towards ampyra. Under the optimized conditions, the calibration curve for ampyra concentration was linear in the range from 0.01 to 40 nmol L−1 with the detection limit of 0.0028 nmol L-1. In addition, the practical analytical performance of the sensor was examined by evaluating the selective detection of ampyra in biological fluids and pharmaceutical samples with satisfied recovery. Therefore, the prepared sensor may hold great promise for fast, simple and sensitive detection and biomedical analysis of ampyra in various real samples
