Micromaterial characterizations of the red cell membrane and block copolymer mimetics

Various aspects of both red cell and polymer membranes were investigated. For red cell membranes, the ability of the red cell\u27s spectrin-actin network to sustain a very large and anisotropic strain was demonstrated in fluorescence-patterned network deformation. Tracking the constrained thermal motions of network-attached nano-particles revealed the softness of the network. The large but constrained thermal motions of the highly extended network suggested a role for the unfolding of spectrin in cell mechanics. For polymer membranes, their robust preparation, stability, and in vitro biocompatibily were demonstrated. The hydration of both polymer and phospholipid membranes quantified by an amphiphilic probe\u27s fluorescence was correlated to micropipette-measured thermomechanical properties. Finally, the fluidity of phospholipid and polymer membranes were measured by fluorescence recovery after photobleaching (FRAP) using confocal laser microscopy