DYES AND INDICATORS USED IN MICROBIOLOGY

Indicator pH AND COLOR
Acid Alkaline
Acid Fuchsin (Andrades) 5.0, pink 8.0, pale yellow
Bromcresol Green 3.8, yellow 5.4, blue
Bromcresol Purple 5.2, yellow 6.8, purple
Bromphenol Blue 3.0, yellow 4.6, blue
Bromthymol Blue 6.0, yellow 7.6, dark blue
Chlorcresol Green 4.0, yellow 5.6, blue
Chlorphenol Red 5.0, yellow 6.6, red
Cresolphthalein 8.2, colorless 9.8, red
m -Cresol Purple 7.4, yellow 9.0, purple
Cresol Red 7.2, yellow 8.8, red
Methyl Red 4.4, red 6.2, yellow
Meta-Cresol Purple (Acid Range) 0.5, red 2.5, yellow
Meta-Cresol Purple (Alkaline Range) 7.4, yellow 9.0, purple
Neutral Red 6.8, red 8.0, yellow
Phenolphthalein 8.3, colorless 10.0, red
Phenol Red 6.8, yellow 8.4, red
Resazurin (Neutral pH) Oxidized: pink Reduced: clear
Thymol Blue (Acid Range) 1.2, red 2.8, yellow
Thymol Blue (Alkaline Range) 8.0, yellow 9.6, blue
Triphenyl-tetrazolium Chloride Oxidized: colorless Reduced: red

REFERENCES

1. Murray, P.R. 1996. ASM Pocket Guide to Clin. Micro ., ASM Press, Washington, D.C.


100796bb