Ordered lipid monolayers, called Langmuir monolayers, are simple, well defined models of the cell membrane. Such films with a desired density can be prepared in a Langmuir-balance. The device consists of a teflon trough, movable barrier(s), electrobalance(s) with Wilhelmy-plate for surface pressure measurement and a PC for control and data acquisition.
Because of the modular nature of the Langmuir monolayer interactions between memrane components can be investigated by measuring average molecular areas. Furthermore membrane affinity of drug candidate molecules or nanoparticles can be determined by injecting the substances below the monolayer and measuring changes in surface pressure over time.