Differential staining

From Wikipedia, the free encyclopedia

Differential Staining is a general term that can refer to a number of specific processes. Generally, it is used to describe staining processes which use more than one chemical stain. Using multiple stains can better differentiate between different microorganisms or structures/cellular componenets of a single organism.

Differential Staining also describes medical process used to detect abormalities in the proportion of different white blood cells in the blood. The process or results are called a WBC differential. This test is useful because many diseases alter the proportion of certain white blood cells. By analysing these differences in combination with a clinical exam and other lab tests, medical professionals can diagnose disease.

One commonly recognizable use of differential staining is the Gram stain. Gram staining uses two dyes: Crystal violet and Fuchsin (the counterstain) to differentiate between Gram-positive bacteria (large Peptidoglycan layer on outer surface of cell) and Gram-negative bacteria.

[edit] Further reading

• http://www.mansfield.ohio-state.edu/~sabedon/black03.htm#differential_stain Detailed Overview of staining
• http://www.uphs.upenn.edu/bugdrug/antibiotic_manual/Gram2.htm The Gram Stain Technique