9622479 Vanderlick A variety of laser-based optical techniques can be used to probe the fundamental properties of the oil-water interface (such as fluctuations), as well as the phase behavior and structure of mono-molecular films which may be residing there. Technologies which depend on mixtures of oils and water rely on a deep understanding of these properties and the materials used to stabilize the interface. The principal investigator recently designed a film balance to manipulate insoluble monolayers (such as phospholipids) residing at the interface between oil and water, thereby controlling the tension of the fluid-fluid interface. This film balance will form the hub of a laser-based experimental station which implements and takes advantage of different optical techniques to probe the statics and dynamics of interfaces with controlled tension. The laser source has already been acquired, and one technique-Brewster Angle Microscopy-is already on-line. A correlater and the necessary optical components to set-up a surface dynamic light scattering (SDLS) apparatus will be acquired with his grant. SDLS provides information on the fluctuations of interfaces, which can be used to determine interfacial tension as well as film rheological parameters. The equipment will be used to study the phase behavior and rheology of lipid and lipid/protein films. ***
