Staining is a technique of microscopy which enhances the contrast of the microscopic image by the addition of chemicals called the stains. Simple staining is the process of staining a cell with one stain or dye. Simple stains provide a quick method of studying the cell shape, size and the arrangement in the given sample. The stain used is a basic, cationic dye which is added over the sample. A cation is a positively charged ion. The cell wall and the cytoplasm of the bacterial cells have a negative charge. So, basic stains like safranin and crystal violet get attracted to the negatively charged cells, bind to the cells and do not get washed away.
