USE

India Ink Control is recommended to be part of quality control to monitor India Ink wet mount preparations.

SUMMARY AND EXPLANATION

India Ink wet mounts are used for the visualization of encapsulated microorganisms, especially Cryptococcus neoformans, directly in clinical specimens. The polysaccharide capsules of organisms will exclude the particles of ink, and the capsules will appear as clear haloes around the organisms on semiopaque backgrounds.

PRINCIPLES

The India Ink Positive Control consists of a suspension of encapsulated Cryptococcus neoformans as a positive control for India Ink wet mount preparations. A suspension of non-encapsulated yeasts is provided as a negative control for India Ink wet mount preparations.

COMPONENT

Positive: Cryptococcus neoformans (encapsulated suspension)

Negative: Yeasts (non-encapsulated suspension)

PRECAUTIONS

This medium is for IN VITRO DIAGNOSTIC USE only. Precautions should be taken against the dangers of microbiological hazards. Specimens, containers, and media should be sterilized after use. This product may contain potentially viable organisms. Handle it as you would a known pathogen.

STORAGE INSTRUCTIONS

Media should be stored at room temperature in the dark and remain in the original packaging until needed.

EVIDENCE OF DETERIORATION

This medium should not be used if the expiration date has passed. If any deficiencies are observed, notify the manufacturer.

OTHER MATERIAL REQUIRED BUT NOT SUPPLIED

The usual clinical microbiological equipment such as India Ink, Nigrosin, slides, coverslips, and microscope, are needed for procedures involving the use of this product.

PROCEDURE

1. Place equal parts of the India Ink Control suspension and India Ink (or Nigrosin) on the slide.

2. Mix well, and add a coverslip.

3. Examine at x100 to x1,000.

EXPECTED RESULTS

The India Ink Positive Control contains capsules that will exclude the ink and appear as clear haloes around the organism.

LIMITATION OF THE PROCEDURES

Results may be hindered if the emulsion with the suspension is too thick, blocking the transmission of light completely.

REFERENCES

1. Murray, P.R. et al. 1995. Manual of Clinical Microbiology, 6th ed. ASM. Washington, DC.