Measuring Lipid Bilayer Permeability with Biomimetic Membranes

Abstract

While there are numerous active mechanisms controlling which molecules cross a cell’s plasma membrane to enter the cytoplasm, these are not the only routes by which molecules can enter cells. In fact, transport by passive diffusion across the lipid bilayer of the plasma membrane represents a nearly universal mechanism of molecular entry. Passive transport represents a key route by which both drugs and environmental toxins can cross biological barriers. Understanding the barrier properties of the lipid bilayer and what molecular characteristics control its permeability is therefore of fundamental interest to toxicology and drug development. Methods of measuring and predicting this permeability have been the topics of research for decades. Today, sophisticated biomimetic cell membranes, coupled with advanced analytical tools and computer modeling, allow new insight into this important biological property.