Département de chimie moléculaire

Tethered bilayer lipid membranes (tBLMs) are designed on mixed self-assembled monolayers (SAMs) of a novel synthetic anchoring thiol, 2,3-di-o-palmitoylglycerol-1-tetraethylene glycol mercaptopropanoic acid ester (TEG-DP), and a new short diln. thiol mol., tetraethylene glycol mercaptopropanoic acid ester (TEG). tBLM formation was accomplished by self-directed fusion of small unilamellar vesicles of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. The influence of the diln. of the anchoring thiol mol. in the SAM on the vesicle fusion process and on the properties of the resulting tBLMs was studied. It is obsd. by quartz crystal microbalance that vesicle fusion is a 1-step process for a pure TEG-DP SAM as well as for mixed SAMs contg. a high concn. of the anchoring thiol. However, upon diln. of the anchoring thiol to moderate concns., this process is decelerated and possibly follows a pathway different from that obsd. on a pure TEG-DP SAM. Electrochem. impedance spectroscopy was used to qual. correlate the compn. of the SAM to the elec. properties of the tBLM. The authors also delineate the necessity of a crit. concn. of this anchoring TEG-DP thiol as a requisite for inducing the fusion of vesicles to form a tBLM. [on SciFinder(R)]