Highly cohesive monolayers of lipid derivatives of colchicine: a dynamics study

Monolayers of lipid derivatives of colchicine spread at the air--water interface reach the thermodynamic equilibrium over an abnormally long period of time. Dynamics of this equilibration and the behavior of the film during compression--decompression cycles are observed by fluorescence microscopy. The thermodynamically disfavored structures observed are unrelated to previously described unusual shapes in the liquid expanded-gas coexistence regions. The relation between the cholesterol-like effect of the colchicinoid moiety, its propensity to dimerize, and the high viscosity of the monolayer are discussed.