Quartz crystal microbalance and electrochemical studies on a viologen thiol incorporated in phospholipid self-assembled monolayers

摘要

Binary self-assembled monolayers (SAMs) were prepared on gold surfaces by use of a viologen, N-methyl-N'-(10-mercaptodecyl)-4,4'-bipyridinium bishexafluorophosphate (V10SH) and a phospholipid, dipalmi-toylphosphatidylthioethanol (DPPTE). Quartz crystal microbalance (QCM) measurements indicated a similar adsorption trend for the V10SH and DPPTE assembling on the gold surface. Well reversible redox waves of V10SH and Fe(CN)(6)(3-/4-) were recorded for the electrodes modified by either pure V10SH SAM or binary SAMs prepared in mixed solutions of V10SH and DPPTE with molar ratios below 1:5. Chronocoulomograms of the SAM-modified electrodes indicated that V10SH acted as an electron-transfer mediator for the Fe(CN)(6)(3-/4-) ions in the electrolyte solution to "gated" access to the electrode surface across the DPPTE monolayer. [References: 41]