Citifluor UVM-3 (a UV Mount medium) is a high refractive index methacrylate- based solution designed to be used with Citifluor AF100 where fluorochrome fading is a problem. The solutions on exposure to light harden to give clear film. Citifluor UVM-3 is totally water miscible and therefore can be used with non-dried specimens e.g. specimens that have been washed in buffer solutions. The light source may either be a desk lamp or sunlight! Since the solution cures to give a hard film there is no need to seal the outer edges of an applied coverslip with nail varnish etc.
The preparation does not contain any volatile solvent but, as with all methacrylate solutions, care should be taken not to spill any of the material onto the skin (use appropriate gloves).
It is important that the Citifluor UVM-3 be only used with specimens that have been fixed i.e. the biopolymers have been cross-linked. The additives in the formulation will dissolve proteins etc. leading to problems with obtaining good images.
The solution is of medium viscosity, is water-white in appearance and easy to apply. It must be stored at 10° C or below and out of strong sunlight. The cap of the bottle should always be replaced after use as a matter of good practice and to prevent inadvertent curing. When used with Citifluor AF100, the ratio of Citifluor UVM-3 to Citifluor AF100 should be 10:1. The rate at which these solutions harden under light will decrease on prolonged storage (> 1 month).