Related Experiment Video
Updated: Aug 16, 2026

Novel Techniques for Observing Structural Dynamics of Photoresponsive Liquid Crystals
Published on: May 29, 2018
Pharmaceutical liquid crystals: the relevance of partially ordered systems
Cynthia L Stevenson1, David B Bennett, David Lechuga-Ballesteros
1Nektar Therapeutics, 150 Industrial Road, San Carlos, CA 94070-6039, USA.
Abstract:
Pharmaceutical solids have generally been characterized as either three-dimensional crystals or amorphous solids based on X-ray powder diffraction and modulated temperature differential scanning calorimetry. In contrast, fewer examples of thermotropic and lyotropic liquid crystals, or mesophases, appear in the pharmaceutical literature, and that literature teaches that the aforementioned analytical techniques should be complemented with polarized light microscopy and small-angle X-ray scattering in order to effectively identify potential liquid crystalline states. Lyotropic liquid crystals are induced by the presence of solvent, and have been extensively described elsewhere in the context of emulsion technology; however, other pharmaceutical examples are emerging. Thermotropic liquid crystals are induced by a change in temperature and are essentially free of solvent, where more pharmaceutical applications appear in the literature. In the present review the general structural characteristics that favor the formation of liquid crystalline mesophases are categorized by therapeutic target and molecular size, and the analytical means of their identification are presented.
Related Concept Videos
Factors Affecting Dissolution: Polymorphism, Amorphism and Pseudopolymorphism
Some polymorphic crystals possess lower aqueous solubility than their amorphous counterparts, leading to incomplete absorption. For instance, the oral suspension of Chloramphenicol, which...
The Colloidal State
Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Two Components: Liquid–Liquid Systems
The Seven Crystal Systems: Overview
Pharmaceutical Alternatives: Polymorphic Form-Related and Particle Size-Related Therapeutic Nonequivalence

