Tethered lipid Bilayers on ultraflat gold surfaces

Tethered lipid bilayers (tBLMs) were obtained by the fusion of liposomes from diphytanoylphosphatidylcholine (DPhyPC) with self-assembled monolayers (SAMs) of a newly designed archaea analogue thiolipid, 2,3-di-O-phytanyl-sn-glycerol-1-tetraethylene glycol-d,l-α-lipoic acid ester (DPTL) on template stripped gold (TSG) films from silicon wafer as a template. SAMs, as characterized by reflection absorption infrared spectroscopy (RAIRS), show a mixture of different conformations of the tetraethylene segment in air, which appears to rearrange into the fully extended conformation when the SAM is immersed into an aqueous electrolyte solution, as deduced from thickness measurements by surface plasmon resonance spectroscopy (SPR). The fusion of liposomes was followed by SPR, quartz crystal microbalance (QCM), and fluorescence microscopy. Highly resistive tBLMs were obtained, as demonstrated by electrochemical impedance spectroscopy (EIS) results, which are equivalent to those for the BLM. This large resistivity i...