Development of ion-channel based biosensors using polymerizable lipids

Abstract

As a step in developing the potential of polymerizable lipids for stabilization of bilayers for biosensor applications, the authors have demonstrated that asymmetric bilayers consisting of one monolayer of polymerized diacetylenic lecithin and the other monolayer consisting of asolectin can support the function of alamethicin, although this function is somewhat modified. Single monolayers of 1, 2-bis- (10, 12-tricosadiynoyl)-sin-glycero- 3-phosphocholine (DC/sub 23/PC) were formed at the air-water interface and polymerized with a low-pressure mercury lamp. Other monolayers were formed from asolectin, and a patch electrode was passed through them to form an asymmetric bilayer. Membrane stabilization in the form of a substantial increase in the bilayer breakdown voltage was seen. When the ion-channel-forming peptide alamethicin was presented to the asolectin monolayer it formed channels through such bilayers, although the turn-on voltage for the channels was substantially higher and the conductivity lower than for symmetric asolectin bilayers.<>