methanol. Store stain in tightly stoppered bottle at 22°C for at least 2 weeks. Dilute stock solution with distilled water (1+9) before use.
R27. Glycerin-Salt Solution (Buffered) Glycerin (reagent grade) 100 ml K2HPO4 (anhydrous) 12.4 g KH2PO4 (anhydrous) 4 g NaCl 4.2 g Distilled water 900 ml
Distilled NaCl and bring volume to 900 ml with water. Add glycerin and phosphates. Adjust pH to 7.2. Autoclave 15 min at 121°C. For double strength (20%) glycerin solution, use 200 ml glycerin and 800 ml distilled water.
R28. Gram Stain (commercial staining solutions are satisfactory)
Hucker's crystal violet Solution A Crystal violet (90% dye content) 2 g Ethanol, 95% 20 ml
Solution B Ammonium oxalate 0.8 g Distilled water 80 ml Mix solutions A and B. Store 24 h and filter through coarse filter paper.