Chemical Sensing with Chemically Modified Electrodes that Mimic Gating at Biomembranes Incorporating Ion-Channel Receptors

Elucidation of the electron transfer mechanism of marker ions at SAMs with charged head groups

“…Inspired by the vocabulary of the biologists and in spite of the above 0022-0728/$ -see front matter Ó 2004 Elsevier B.V. All rights reserved. doi:10.1016/j.jelechem.2004.07.026 mentioned differences, the notion ''ion channel (mimetic) sensor'' has not only been used for sensors based on gating the flow ions but also for sensors based on gating of the electron flow [2,3]. The latter ''ion gate sensing'' was originally described by Sugawara et al almost two decades ago [4].…”

Ion-Channel – Mimetic Sensors Based on Self-Assembled Monolayers of Phosphate Esters: High Selectivity for Trivalent Cations

“…While at low Ca 2 concentrations no peak was observed within the potential window of the CV, at high Ca 2 concentrations a reduction and an oxidation peak appeared. At the highest Ca 2 concentration of 10 mM, the peak separation for the Fe(CN) These results suggest that in the absence of Ca 2 electrostatic repulsions between the anionic marker species Fe(CN) 3À 6 and negatively charged, deprotonated phosphate groups on the electrode surface prevent the access of the marker to the electrode. Binding of Ca 2 to the phosphate ester groups reduces the excess negative charge density on the monolayer and facilitates the access of the anionic marker to the electrode, resulting at high Ca 2 concentrations in a nearly reversible redox reaction.…”

“…6). In the case of the latter type of sensors, mainly electrostatic interactions between the marker ions and the receptor monolayer seem to determine how easily the marker can access the electrode.…”

A New Kind of Potassium Sensor Based on Capacitance Measurement of Mimic Membrane

“…There are many methods for detecting potassium ion for its leading role in membrane transport [8,22,23]. However, there is a need for fast, easy, and reliable methods for the detection of potassium ion.…”