Application Sheet for CitiFluor™ AF4 Mountant Solution
EMS Catalog #17973-25
AF4 is a mountant solution composed of glycerol and the antifadent n-propyl gallate. N-Propyl gallate is a well established antifadent and is particularly useful for stopping the photobleaching of DAPI, Hoechst and Alexa dye stained materials, as well as FITC labeled materials. It is ideal for examining tissue sections and dead cells. An aqueous solution (75% AF4 to 25% water v/v) has a pH of ~5. Since many fluorochromes exhibit their maximal fluorescent intensity at higher pH values the AF4 should be mixed with an appropriate buffer solution. The resulting solutions may start to show discoloration within a few hours and therefore buffered AF4 solutions should be made up as and when required. The mountant solution should be pipetted onto the specimen (which has been copiously washed with the appropriate buffer) and then a cover slip applied. If the slides are stored in a refrigerator, the viscosity of the mountant solution increases thereby helping to keep the cover slip in place. There is no need to seal the cover slip with nail varnish.
Properties and Storage of AF4 Mountant Solution
The solution is of medium viscosity and has a water-white in appearance. It may be stored at room temperature and ideally between 50° and 150° and out of strong sunlight. The cap of the bottle or if using the pipette supplied with the material, the cap which covers the pipette delivery point, should always be replaced after use as a matter of good practice and also to prevent the ingress of water (due to the glycerol being hygroscopic). Samples stored under these conditions for 6 months have shown no apparent deterioration. If the AF4 solution is being used in an assay, a control experiment should always be carried out.