Drying colloidal systems: laboratory models for a wide range of applications

The drying of complex fluids provides a powerful insight into phenomena that take place on time and length scales not normally accessible. An important feature of complex fluids, colloidal dispersions and polymer solutions is their high sensitivity to weak external actions. Thus, the drying of complex fluids involves a large number of physical and chemical processes. The scope of this review is the capacity to tune such systems to reproduce and explore specific properties in a physics laboratory. A wide variety of systems are presented, ranging from functional coatings, food science, cosmetology, medical diagnostics and forensics to geophysics and art

Enantiomeric resolution and chiral recognition of racemic nicotine and nicotine analogs by .beta.-cyclodextrin complexation. Structure-enantiomeric resolution relationships in host-guest interactions

High-performance liquid chromatography using β-cyclodextrin bonded phases was examined for the enantiomeric separation of racemic nicotine and 19 racemic nicotine analogues. Ten pairs of enantiomers were separated by this technique. This represents the first reported facile and direct separation of these racemates. Effects of pH, mobile phase composition, and structural features of the substrates (i.e., position and size of substituents, presence of pyrrolidine ring or hydrogen bonding functionalities, basicity) on the enantioselectivity are examined. Various structural aspects of the compounds were related to retention to the cyclodextrln-modlfied support and to the enantiomeric separations observed. Implications of this work to host-guest complexation are discussed. © 1988, American Chemical Society. All rights reserved