Gold electrodes modified with 11-mercaptoundecanol were used as substrates for immobilization of ferrocenecarboxylic acid molecules, which act as redox sites. The attachment of the ferrocenecarboxylic acid molecules to the monolayer surface involved the formation of covalent bonds or hydrogen bonds. These systems were designed for the investigations of the kinetics of mediated electron transfer. We report the comparative electrochemical studies of electron transfer through self-assembled monolayers with covalently bonded and hydrogen bonded electroactive groups. We found that the rate of electron transport through hydrogen bonded interface is only slightly lower than for covalently bonded system. (C) 2005 Elsevier Ltd. All rights reserved.