Mounting media

The choice of the mounting medium usually obviates the need for any new instmmental technique for enhancing contrast. A particle mounted in a... 

Figure 3.9 Small tubercle cross section. The steel surface is at the bottom, and the red material is an epoxy mounting medium. Note the small, shallow central cavity. (Magnification 7.5x.)...

After washing 3x with PBS, place coverslips on slides with a drop of Vectashield mounting medium for fluorescence (Vector Laboratories, CA). 

In all microscopic methods, sample preparation is key. Powder particles are normally dispersed in a mounting medium on a glass slide. Allen [7] has recommended that the particles not be mixed using glass rods or metal spatulas, as this may lead to fracturing a small camel-hair brush is preferable. A variety of mounting fluids with different viscosities and refractive indices are available a more viscous fluid may be preferred to minimize Brownian motion of the particles. Care must be taken, however, that the refractive indices of sample and fluid do not coincide, as this will make the particles invisible. Selection of the appropriate mounting medium will also depend on the solubility of the analyte [9]. After the sample is well dispersed in the fluid, a cover slip is placed on top... 

To each slide, apply one or two drops of non-aqueous mounting medium to the uncovered tissue and apply the coverslip. Apply the coverslip at an inclined angle to the slide, and lower it gently to avoid trapping air bubbles. 

Add one or two drops of aqueous mounting medium to the stained tissue and apply the coverslip. 

Mounting mount sections in an anti-fade medium for fluorescence microscopy. The authors have a good experience with Vectashield mounting medium from Vector Laboratories (http //www.vectorlabs.com/). 

Rinse in distilled water and mount with an aqueous mounting medium, or proceed further with steps 5, 6 and 7. 

Mount with xylene-based mounting medium, like Canada balsam or DPX however, aqueous medium can also be used (see Sect. 3.5). 

Glycerol mounting medium (90% glycerol, 10% PBS), or commercial glycerol mounting medium (Difco, Detroit, MI). 

Mount the cells under glycerol mounting medium under a no. 1 covershp as shown in Fig. 2 (see Notes 6-9). 

Transfer the animal to the larger coverslip (24 x 60 mm), and pipet away the PBS. Add one drop of monnting medium. Lower the smaller coverslip (22 mm ) onto the animal. Use forceps first to pnt one side of the coverslip into the mounting medium and then to lower the coverslip slowly allowing any air bubbles to be pushed to the edge. Avoid dropping the coverslip onto the animal since there will surely be many air bubbles trapped beneath it (see Note 11). 

Add an aqueous mounting medium or an antifade solution, mount a coverslip and analyze using fluorescent microscopy with a fluorescein filter. 

Permount mounting medium (Fisher Scientific, Pittsburgh, PA). 

Glycerol-gel mounting medium containing an antifading agent (Vectashield Vector). 

Antiavidin antibody solution (Vector Labs) 5 pg/mL in PBS with 1% Tween-20. Propidium iodide (Sigma, St. Louis, MO) counter stain 1 pg/mL in PBS. Antifade mounting medium 100 mg p-phenylenediamine dihydrochloride in 10 mL PBS adjust to pH 9 (see Note 3). 

Mount the slides in a water soluble mounting medium (e.g., Aqua mount). Observe under the light microscope (see Fig. 1). 

Finally, microscopic examination of samples often requires their preparation as cross sections or thin sections, or by mounting the sample on a glass slide by means of a mounting medium. For preparing thin and cross sections, samples are embedded in a polymer solution. After curing of the polymer, the thin or cross section is obtained by polishing the embedded sample with SiC abrasive disks. Aluminum suspensions or diamond paste are occasionally employed in a final polishing step. 

Mounting medium distrene, tricresyl phosphate, xylene (DPX)... 

BECKE TEST. A microscope of moderate or high magnification is used to compare the indices of refraction of two contiguous minerals for of a mineral and a mounting medium or immersion liquid), in a thin section or other mount. When the two substances differ substantially in refractive index, they are separated by a bright line, called the Becke line. The line moves toward the less refractive of two materials when the tube of the microscope is lowered. 

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