Gallium replication in aquatic and nonaquatic organism scanning electron microscopy

A technique using pure gallium metal as a replication material is reported for biological surface scanning electron microscopy (SEM). The technique first directly enables aquatic organisms in water to be replicated due to galliumʹs low melting point and, second, reproduces surface structures and images of the two-dimensional (2D) distribution of substances transferred from the original surface to the gallium surface due to galliumʹs high surface tension. An aquatic protozoan in water was directly replicated to show its typical surface structures. The technique was then used to visualize human hair surface structures and 2D transferred substance distribution using X-ray microanalysis.