Ultrasensitive determination of the chiral nature of a molecule is important for fully understanding protein and DNA structures, and for the design, synthesis and purification of drug molecules. Consequently, development of ultrasensitive detection of chiral molecules is a grand challenge and at the heart of many of today's research fields, including chemistry, biology, biotechnology and pharmacology. Here a novel method afforded by electrochemically tracing the Cu2+ ions that are replaced by (L/D)-carnitine on an(L/D)-cysteine modified gold electrode is described. The electrochemical signal of copper ionswas monitored, these were immobilized on the (L/D)-cysteine functionalized gold electrode surface via cooperative metal-ligand interaction, followed by replacing the Cu2+ with (L)-carnitine or (D)-carnitine chiral molecules based on the hetero-or homo-chiral interaction between carnitine and cysteine molecules. The results illustrated that the Cu2+ replacement ratio between (L/D)-carnitine and (D/L)-cysteine were higher than that between (L/D)-carnitine and (L/D)-cysteine, which is consistent with previous studies that heterochiral interaction is stronger than homo-chiral interaction. This study demonstrates a facile, but innovative electrochemical method to probe the chiral recognition of carnitine molecules. (C) 2017 Elsevier Ltd. All rights reserved.