| MadSci Network: Molecular Biology |
The answer depends on what you want to use the stain for. Normally you can dilute with pure, double distilled water. If you need to keep the soultion basic, as for Loeffler's Methylene Blue Stain used in histology, then use a bit of KOH. Here are the official recipies taken from the Bacteriological Analytical Manual, 8th Edition, Revision A, 1998 and other sources. See also: This link at FDA Methylene blue stain ----------------------------------------- 0.3 gm Methylene blue 30 ml 95% ethanol 100 ml distilled water Dissolve stain in alcohol, then dilute with water and filter Methylene Blue, Loeffler's ----------------------------------------- 0.3 gm Methylene blue 30 ml 95% ethanol 70 ml Dilute KOH
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