Antineoplasic Drug Methotrexate Redox Mechanism Using a Glassy Carbon Electrode

Methotrexate (MTX) is an antimetabolite of folic acid indicated in the treatment of a variety of cancers. The electrochemical behaviour of MTX on a glassy carbon electrode was investigated. The MTX oxidation is a complex, pH-dependent, diffusion-controlled irreversible process and proceeds with the transfer of two electrons and two protons and the formation of one electroactive product, 7-hydroxymethotrexate that undergoes a reversible redox reaction. The MTX reduction is a pH-dependent, quasi-reversible process and involves the transfer of two electrons and two protons leading to the formation of an electroactive product.