Mediated Electron Transfer Across Supported Bilayer Lipid Membrane with TCNQ-Based Organometallic Compounds

Supported bilayer lipid membrane (s-BLM) containing one-dimensional compound 1, TCNQ-based (TCNQ = 7,7,8,8-tetracyanoquinodimethane) organometallic compound {(Cu-2(mu-Cl)(mu-dppm)(2))(mu(2)-TCNQ)}(infinity), was prepared and characterized on the self-assembled monolayer (SAM) of 1-octadecylmercaptan (C18H37SH) deposited onto Au electrode. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results showed that the compound 1, dotted inside s-BLM, can act as mediator for electron transfer across the membrane. Two redox peaks and the charge-transfer resistance of 400 k Omega were observed for compound I inside s-BLM. The mechanism of the electron transfer across s-BLM by TCNQ is by electron hopping while TCNQ-based organometallic compound is by conducting. Further conclusion drawn from this finding is that the TCNQ-based organometallic compound embedded inside s-BLM exhibits excellent electron transfer ability than that of free TCNQ. This opens a new path for the development of s-BLM sensor and/or biosensor by incorporation with TCNQ-based organometallic compounds.