Mounting Medium with DAPI ab104139 (previously called Fluoroshield Mounting Medium With DAPI) is an aqueous anti-fade mounting medium designed to preserve fluorescence when imaging tissues and cell samples. It is fortified with DAPI as a counter-stain for DNA (DAPI also stains RNA).

The formulation prevents rapid photobleaching of FITC, Texas Red, AMCA, Cy2, Cy3, Cy5, Alexa fluoro 488, Alexa fluoro 594, Green fluorescent protein (GFP), tetramethyly rhodamine, R-Phycoerythrin (R-PE), Phyocyanin (PC), and Allophycocyanin (APC).

Fluorescence is retained during prolonged storage at 4°C in the dark. This medium does not contain phenylenediamine, which destroys immunofluorescence of Cy dyes, R-PE, PC and APC.

Mounting media products

For fluorescent cell and tissue staining, Abcam recommends aqueous, anti-fade Fluorescence Mounting Medium ab104135, Mounting Medium with PI ab104129, and this product, Mounting Medium with DAPI ab104139. For thick sections or tissues containing lots of fat, we recommend Glycerol Mounting Medium with DAPI ab188804.

For chromogenic immunohistochemistry, such as with DAB, AEC, or Fast Red, we recommend aqueous Mounting Medium ab64230, or organic Limonene Mounting Medium ab104141. 

Procedure

- Bring the vial to room temperature.

- Rinse slide to be mounted with distilled or deionized water, touch the edges of slide on a paper towel to remove excess water. Place slides on a flat surface.

- Turn the vial upside down and open the dropper to remove any air bubbles.

- Apply 3-4 drops of mounting medium directly on top of the specimen and spread out evenly by tilting slide back and forth or spread evenly with a 0.2 ml plastic pipette tip making sure the tissue is not touched. Excess medium can be removed by touching the edges of slide against paper towel.

- Let stand at room temperature for about 5 minutes.

- Apply cover slip carefully avoiding air bubbles.

- The specimen is ready for visualization under a microscope.

Seal the edges of cover slip with nail polish, any organic medium or Limonene mounting medium ab104141. If a coverslip is not sealed, air bubbles will appear in a few days.

Store the slide in the dark at 2-8°C.

Removal of Coverslip
Coverslip can be removed before sealing the edges. Soak slide in warm (37°C) distilled or deiononized water for several minutes. Carefully and slowly move the coverslip. Soak in water for an additional few minutes to remove coverslip. Rinse slide several times with warm water to remove all mounting medium. The slide can be remounted again.

Refractive Index
1.364 ± 0.002. This number applies to this mounting medium in solution. Refractive indexes change when the water solvent evaporates and mounting media dries on slides. We do not have the means to measure the refractive indexes of dry mounting mediums; however we expect the numbers to go higher when dried. The refractive index of water is 1.3330.