Biomolecular Mask Formation Using UV Patterened Sam Films

摘要

The research focus has been on the challenging issues involved in achieving, two-dimensional recrystallization of protein (S-layer) monomers in large (-several hundred micron) single crystal areas. To acquire facility with the recrystallization process we first explored the experimental conditions which influence protein crystallization e.g., protein concentration. temperature, pH, ionic strength concentration of various mono- and divalent cations, etc. We attempted crystallization experiments in aqueous suspension or at the air/water interface before trying to reassemble protein monomers directly on a patterned surface. We were able to obtain large (- 1 micro x 2 micro), well-ordered, recrystallized protein patches following dialysis. As with the native protein crystal, the recrystallized S-layers showed a square lattice with lattice parameter of 13 nm. We established a reproducible protocol for preparing a solution of S-layer monomers for a recrystallization experiment. We used both thin film carbon substrates on transmission electron microscope (TEM) grids as well as bulk silicon substrates for a variety of diagnostic recrystallization experiments. Protocols for these experiments were established and numerous experiments carried out, including; grid modification: float, touch, and time; gluteraldehyde crosslinking of S-layer crystal; and floatation of the formvar directly on the recrystallization solution. We attempted to extrapolate from our work with TEM grids to recrystallization experiments directly on Si wafers.