Multilamellar

Multilamellar is an adjective describing an object that consists of many lamellae, thin plate-like layers, often arranged in concentric shells or stacks. The term is used across scientific fields to denote multi-layered, lamellar architectures.

In biology and medicine, multilamellar structures frequently appear as organelles or delivery systems. Multilamellar bodies are intracellular structures containing multiple lipid bilayers and are involved in lipid storage and turnover in various cell types. In the lung, lamellar bodies are secretory organelles in type II pneumocytes that store and secrete pulmonary surfactant, contributing to surface tension regulation. In pharmacology and nanomedicine, multilamellar vesicles (MLVs) are lipid vesicles composed of several concentric phospholipid bilayers separated by aqueous layers. MLVs can encapsulate hydrophilic and hydrophobic compounds and are used in drug delivery and cosmetics, though they tend to be less stable and release cargo more slowly than unilamellar formulations. Common preparation methods include thin-film hydration and reverse-phase methods, followed by sizing and sometimes extrusion.

In materials science and related fields, multilamellar describes layered materials such as clays, graphite, and layered double hydroxides, where lamellae create a stacked, anisotropic architecture. Such structures are exploited in barrier coatings, catalysis, intercalation chemistry, and nanocomposites due to their mechanical strength and controlled interlayer spacing.

Characterization of multilamellar systems often uses transmission electron microscopy or cryo-electron microscopy, complemented by SAXS or DLS to assess layer spacing and size distribution.