Cell staining is a technique used for the better visualization of cells and their parts under the microscope. By using different stains or dyes, the nucleus of a cell can be viewed easily through a microscope. Most of the stains can be used on non-living or fixed cells, while only some specific types of stains can be used on the living cells.
Sometimes, cells are also stained to highlight the metabolic processes of the cells or to differentiate between living and dead cells in the given sample. The reason that cells are stained is that the dye used to stain a cell makes it possible to view the cell and its components under a microscope which cannot be seen with bare eyes. You can buy high-quality cell staining kits to view them properly under a microscope.
Cell staining techniques and preparation completely depends on the type of stain used. Different procedures can be used to prepare a sample like permeabilization in which the cells are treated with a mild surfactant, which dissolves the membranes of the cell which allows large dye molecules to enter inside the cell.
Another technique is fixation in which the cells are preserved by adding a chemical fixative that creates a chemical bond between proteins which increases their hardness. Common fixatives that are used here are formaldehyde, ethanol, or methanol. Another procedure is mounting in which the samples are attached to a glass slide for observation and analysis.
Thin slices of materials such as tissues are applied to a slide for observation. The last one is staining in which the sample is dipped into a dye solution and then rinsed and observed under a microscope. After this, the extra dye is washed away.