Citifluor AF2 is a mountant solution composed of glycerol and an antifadent. It was specifically designed to stop the photo bleaching of the fluorescein moiety of FITC labelled biological specimens. Its application is not however limited to FITC labelled materials and has been used with advantage with many other fluorochromes including rhodamines and DAPI. It is ideal for examining tissue sections and dead cells. An aqueous solution (75%AF2 to 25% water v/v) has a pH of ~10. The solution should be pipetted onto the specimen and then a cover slip applied. If the slides are stored in a refrigerator, the viscosity of the mountant solution increases thereby helping too keep the cover slip in place. There is no need to seal the cover slip with nail varnish. Specimens mounted in Citifluor AF2 solutions have been kept in this way for many months without suffering damage.
The solutions are of medium viscosity and are water-white in appearance. They may be stored at room temperature and ideally between 5° and 15° and out of strong sunlight.. Samples stored under these conditions for 6 months have shown no apparent deterioration. If the Citifluor AF2 solution is being used in an assay, a control experiment should always be carried out.
If the viscosity of the Citifluor AF2 solution is too high for your purposes, it may be admixed with either Citifluor AF1 or Citifluor AF3 mountant solution. As the amount of Citifluor AF1 or Citifluor AF3 solution is increased so the viscosity decreases.