| Abstract
| - Recently, tethered bilayer lipid membranes (tBLMs) have shown high potential as biomimetic systems due to theirhigh stability and electrical properties, and have been used in applications ranging from membrane protein incorporationto biosensors. However, the kinetics of their formation remains largely uninvestigated. By using quartz crystalmicrobalance with impedance analysis (QCM-Z), we were able to monitor both the kinetics and viscoelastic propertiesof tether adsorption and vesicle fusion. Formation of the tether monolayer was shown to follow pseudo-first-orderLangmuir kinetics with association and dissociation rate constants of 21.7 M-1 s-1 and 7.43 × 10-6 s-1, respectively.Moreover, the QCM-Z results indicate a rigid layer at the height of deposition, which then undergoes swelling asindicated by AFM. The deposition of vesicles to the tether layer also followed pseudo-first-order Langmuir kineticswith observed rate constants of 5.58 × 10-2 and 2.41 × 10-2 s-1 in water and buffer, respectively. Differential analysisof the QCM-Z data indicated deposition to be the fast kinetic step, with the rate-limiting steps being water releaseand fusion. Atomic force microscopy pictures taken complement the QCM-Z data, showing the major stages of tetheradsorption and vesicle fusion, while providing a road map to successful tBLM formation.
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