Morrin, AoifeMoutloali, Richard M.Killard, Anthony J.2023-06-062023-06-062004Morrin, A. et al. (2004). Electrocatalytic sensor devices: (I) cyclopentadienylnickel(II) thiolato Schiff base monolayer self-assembled on gold. Talanta, 64 (1) , 30-38. https://doi.org/10.1016/j.talanta.2003.11.0461873-3573https://doi.org/10.1016/j.talanta.2003.11.046http://hdl.handle.net/10566/9034The fabrication of a self-assembled monolayer (SAM) of a cyclopentadienylnickel(II) thiolato Schiff base compound, [Ni(SC6H4NC(H)C6H4 OCH2CH2SMe)( 5-C5H5)]2 on a gold electrode is described. Effective electronic communication between the Ni(II) centres and the gold surface was established by electrochemically cycling the Schiff base-doped Au electrode in 0.1 M NaOH from −200 mV to +600 mV. The SAM-modified electrode exhibited quasi-reversible electrochemistry. The integrity of this electrocatalytic SAM, with respect to its ability to block and electro-catalyse certain Faradaic processes, was interrogated using cyclic voltammetric experiments. The formal potential, E◦ , varied with pH to give a slope of about −30 mV pH−1. The surface concentration, G, of the nickel redox centres was found to be 1.548 × 10−11 mol cm−2. By electrostatically doping the SAM using an applied potential of +700 mV versus Ag/AgCl, in the presence of horseradish peroxidase (HRP), it was fine-tuned for amperometric determination of H2O2. The electrocatalytic-type biosensor displayed typical Michaelis–Menten kinetics and the limit of detection was found to be 6.25 mM. © 2004 Elsevier B.V. All rights reserved.enChemistryBiosensorElectrostatic dopingTechnologyArticle