How is the plasma membrane visualized?
Posted January 20, 2022
The plasma membrane can be visualized by electron microscopy or fluorescence microscopy using appropriate labels. Most dominant plasma membrane labels include:
Lipophilic Tracers such as DiI, DiD, DiA, DiR, DiO, and DiS - These are a family of dialkyl carbocyanine dyes commonly used for staining hydrophobic structures such as the plasma membrane. These dyes diffuse quickly and laterally within the plasma membranes resulting in detailed and uniform staining of the entire cell surface, enabling researchers to visualize the plasma membrane clearly.
Fluorescently labeled lectin such as Wheat germ agglutinin (WGA) - Its high affinity for N-acetyl-D-glucosamine and sialic acid residues on glycoconjugates makes this a useful dye for visualizing plasma membranes of mammalian cells, yeast bud scars, and gram-positive bacteria. It can also be used to visualize the plasma membrane in skeletal and cardiac sarcolemma and fibrotic scar tissue.
Fluorescent probes of DiIC12, DiD, DiIC18, FM4-64, BD-SM, LRB-PE, and Laurdan – These labels have bright fluorescence with high signal-to-noise ratios and high photostability, which makes them suitable for visualizing plasma membranes in suspended or attached live cells. Staining is well-retained in the plasma membrane after fixation.