Gram stain reagents

  Gram stain reagents

These stains can be ordered as a complete kit from VWR (#l5204-004) or can be reconstituted as follows:

 

Crystal violet

crystal violet (90% dye content)                            20.0 g

ethanol (95%)                                                         200 mL

ammonium oxalate                                                 8.0 g

dH₂0                                                                       800 mL

Mix  first  two  ingredients  and  let  sit  overnight  or  until  dye  goes into solution.     Add remaining ingredients and filter before use.

Gram's iodine

iodine crystals                                                        1.0 g

potassium iodide                                                    2.0 g

dH₂0                                                                       300 mL

                    

Decolorizer

acetone                                                                   40 mL

ethanol (95%)                                                         60 mL

                    

Safranin

safranin O                                                               2.5 g

95% ethanol                                                           100 mL

dH₂0                                                                       900 mL

Filter safranin solution before use.