Index >> Staining Methods in Microbiology >> Dry India Ink Film

(a) Dry India ink film
This is a negative staining technique, where background is stained. When this preparation is examined microscopically with low intensity of light a phase like effect is observed. Capsules appear as halo or light ring around each cell against dark background. The sequence of steps described by But et al (18) is as under. Emulsify small amount of bacterial culture in a loopful of 6% glucose solution at one end of a slide. Add loopful of 8% aqueous solution of nigrosin and mix.