The cell and a light violet color of the capsule. Here, one will see a dark violet color of Ultimately results in the diffusion of a stain towards the outer surface of theĪfter the slide is air dried, it becomes possible to observe the stain (copper sulfate) for the purposes of creating an ionic difference that Here, the smear/sample is treated with a hypertonic solution This is a positive staining method used inĬapsule staining. Microscope stage and observe using oil immersion With Anthony’s stain method, the primary stainĪnd at an angle, spread the drop and sample to form a thin film Gives a more even background and spreads more easily. * Nigrosin is recommended to India ink because it Taken the crystal violet dye while the capsule will be clear against a dark Will be dark as a result of India ink, bacteria cells will be purple having When viewed under the microscope, the background On the other hand, crystal violet is used for number of reasons including: Nature, India ink (or Congo red, nigrosin) stains the background dark. This is a negative staining technique that isĮssentially used to identify the presence of capsules. However, some of the other stains that can also be used include: India ink is often used as the negative stain. Spread out the drop into a film to have a thin layer of the smear-ink mixtureĬrystal violet for a minute and then tilt the slide to drain excess dye Glass slide and having laid it at an angle on one end of the first slide, Obtain a sample and place it onto the slide and mix it with the drop of India Two of the most commonly used methods used in It becomes necessary to stain the background using an acidic stain while the It's worth noting that for most part, capsules are non-ionic.Īcidic and basic stains will often fail to adhere on to them. Which involves the use of two stains primary stain and the counterstain. Some of the organisms that are likely to have aĬapsule stain is a type of differential stain Some of the other significance of a capsule This is achieved due to the fact that the capsule is very smooth and has a negative charge that prevents attachments/adherence. For some bacteria, capsules are very important in that they are a major virulence factor.Īs such, they protect the bacteria from phagocytic actions of such cells as neutrophils allowing the bacteria to thrive. They may also be composed of a number of other materials such as poly-D-glutamic acid.

Typically, a capsule is composed of capsular polysaccharides (CPS) which are polysaccharides. Material that may form on the surface of a cell wall of other bacteria is theįact that capsules are well organized layers that cannot be easily washed off. What really differentiates a capsule from any other Well organized layer of material lying outside the cell wall referred to as aĬapsule (or K antigen). Some bacteria like Bacillus anthracis have a

Red india ink