Confocal Microscopy Imaging of Protein Adsorption to the Gas Liquid Interface

In this presentation a novel confocal imaging technique is described which allows for the visualization and therefore measurement of the surface concentration as a function of time during the adsorption process. Here, the primary interest is in blood protein adsorption to the gas liquid interface. Two fluorescently labeled proteins are used in the experiments, a bovine serum albumin-Texas Red (BSA-TR) conjugate and a human fibrinogen-Oregon Green (HF-OG) conjugate. Single protein solutions, two-protein solutions, and Pluronic PF-127 and HF-OG solutions are investigated. The method does not require any a priori knowledge of protein orientation or conformation at the interface, and thus is a large first step toward a simple and reliable method to measure and compare surface concentrations during protein adsorption.