Solution boundaries, solid/protein

The combination of physical and chemical boundary conditions defines how the silk protein solution turns into a solid silk thread consisting of highly oriented molecules and hierarchically organized structures. 

As indicated in my report, we now know the rates of lateral diffusion of phospholipids in lipid bilayers in the fluid state, and in a few cases the rates of lateral diffusion of proteins in fluid lipids are also known. At the present time nothing is known about the rates of lateral diffusion of phospholipids in the crystalline, solid phases of the substances. As mentioned in my report, there are reasons to suspect that the rates of lateral diffusion of phospholipids in the solid solution crystalline phases of binary mixtures of phospholipids may be appreciable on the experimental time scale. Professor Ubbelohde may well be correct in pointing out the possibility of diffusion caused by defects. However, such defects, if present, apparently do not lead to significant loss of the membrane permeability barrier, except at domain boundaries. 

Only the methods used in this study (i, 2, 3) can detect and follow the initial events at the boundary between a solid substrate and the biological milieu. This extraordinary sensitivity derives from the ability to monitor events from within the substrate itself by making the substrate capable of supporting multiple attenuated internal reflection (MAIR) at a variety of useful spectroscopic wavelengths. In other studies, it was concluded that adsorbed protein on solid substrates is of essentially native i.e. solution or volume phase) conflguration and present in signiflcant thickness (6). Those studies used a different version of the internal reflection spectroscopic method wherein a prism element was forcefully... 

Figure 2 Popular discretization schemes for numerical solution of the Poisson-Boltzmann equation. The solid black line and circles denote a model protein other lines denote the mesh on which the system is discretized, (a) Finite difference, (b) Boundary element, (c) Finite Element, (d) Focusing on finite difference grids. See color insert.

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