Electric-field triggered controlled release of bioactive volatiles from imine-based liquid crystalline phases.
Application of an electric field to liquid crystalline film forming imines with negative dielectric anisotropy, such as N-(4-methoxybenzylidene)-4-butylaniline (MBBA, 1), results in the expulsion of compounds that do not participate in the formation of the liquid crystalline phase. Furthermore, amines and aromatic aldehydes undergo component exchange with the imine by generating constitutional dynamic libraries. The strength of the electric field and the duration of its application to the liquid crystalline film influence the release rate of the expelled compounds and, at the same time, modulate the equilibration of the dynamic libraries. The controlled release of volatile organic molecules with different chemical functionalities from the film was quantified by dynamic headspace analysis. In all cases, higher headspace concentrations were detected in the presence of an electric field. These results point to the possibility of using imine-based liquid crystalline films to build devices for the controlled release of a broad variety of bioactive volatiles as a direct response to an external electric signal.
Herrmann
Andreas
A
Firmenich SA, Division Recherche et Développement, 1 route des Jeunes, B.P. 239, 1211 Genève 8, Switzerland.
Giuseppone
Nicolas
N
Lehn
Jean-Marie
JM
D016880:Anisotropy; D020650:Combinatorial Chemistry Techniques; D003517:Cyclopentanes / Q000737:chemistry; D003692:Delayed-Action Preparations; D004574:Electromagnetic Fields; D007097:Imines / Q000737:chemistry*; D050866:Liquid Crystals / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D014835:Volatilization
D003517:Cyclopentanes; D003692:Delayed-Action Preparations; D007097:Imines; C016327:cyclopentanol