Fast and easy method of lanthanoid staining for visualization of cellular ultrastructure and spatial arrangement

Considering the demand for investigating spatial cell arrangement within a scaffold, yet unsatisfied, we aimed at developing a new method of sample preparation for SEM that would, besides other things, allow visualization of cellular ultrastructure and deliver from toxic chemicals and artifacts. A combination of BSE imaging in a low-vacuum mode with supravital lanthanoid staining has yielded highly informative images that contain many of the subsurface cell structures, particularly, intercellular contacts, cell membranes, nuclei with nucleoli, mitochondria, endoplasmic reticulum, and cytoskeleton. Moreover, the developed approach provides an idea of three-dimensional arrangement of cellular elements with a greater depth of focus than that of optical methods, which is drastically important for fulfilling the needs of tissue engineering. Being fast and simple, the method is able to change the whole concept of using SEM in biomedical studies.