The New Bilayer Lipid Membrane System: Prospects for Applications in Biomolecular Electronic Devices

Abstract

The bilayer lipid membrane (BLM) system has been extensively investigated as a model of biological membranes since the early 1960s. However, until recently, relatively few attempts have been made to exploit their potential in practical applications such as sensors and molecular devices. From the viewpoint of membrane biophysics and physiology, biological membranes are essentially the basic structure of nature’s sensors and devices. As examples: the thylakoid membrane of green plants functions as an energy transducer, converting sunlight into electrical/chemical energy; in visual perception, the photoreceptor membrane of a rod’s outer segment detects photons; and the plasma membranes of cells and organelles possess the ability to sense ions, for instance differentiating Na+ and K+ with great specificity. Further, the plasma membrane provides sites for a host of ligand receptor contact interactions such as antigen-antibody formation. In view of the fact that these and numerous other vital functions are associated with cell membranes, it is not surprising that the past two decades or so have witnessed an enormous research effort directed toward membranes. Reconstituted planar BLMs and spherical liposomes have played a primary role in this research. In this paper, a new BLM system is described, which, with its ease of formation, its stability, and its long life, offers new possibilities for applications in biosensors and molecular electronics.