Cover slip

Small fibres should be manipulated against a dark—preferably black—background, and small camel s-hair brushes moistened with water are very convenient implements. Fibres, when examined under a microscope, become more easily visible if they are mounted imder a cover slip and a drop of glycerine, coloured by a dye, is allowed to run in. 

The interference pattern depends both on the symmetry of the liquid crystal mesophase and on the arrangement of the molecules between the glass cover slips. Three examples are given in Fig. 8. 

Direct wet mounts are prepared by placing a small drop of 0.85% saline toward one end of a glass slide (2 by 3 in. [ca. 5 by 7.5 cm]) and a small drop of appropriate iodine solution (see below) toward the other end. With an applicator stick, a small portion of specimen (1 to 2 mg) is thoroughly mixed in each diluent, and a no. 1 cover slip (22 mm) is added. The density of fecal material should be such that newspaper print can be read with difficulty through the smear. The material should not overflow the edges of the cover slip. Grit or debris may prevent the cover slip from seating and may be... 

With a loop which is bent at a right angle, transfer to a slide (2 by 3 in.) two loops of surface material beside 1 drop of saline and two loops beside 1 drop of iodine. With the heel of the loop, mix first the saline and then the iodine with the surface material. Cover each mixture with a 22-mm no. 1 cover slip. The slide should be made within 20 min. 

To retard drying, place each prepared slide on a bent glass rod or portions of applicator sticks in a petri dish containing a damp paper towel. Petri dishes may be placed in the refrigerator if examination will be delayed. Alternatively, cover slips may be sealed with Vaspar. 

Remove the top portion of the sample with a wire loop bent at a right angle. Place several loopfuls on a glass slide (2 by 3 in.). Cover the specimen with a 22-mm cover slip, and examine the slide with a X 40 objective. Oocysts are found just beneath the cover slip and are refractile. Saline or iodine is not used in the preparation of these mounts. 

Permanently stained slides may be mounted with a cover slip or may be air dried and examined after oil is added. Slides should be examined at a magnification of x400 to X500 or greater after they are scanned under lower power to find optimal areas. A x50 oil immersion objective is particularly helpful, as it allows the easy use... 

Should the stain be unsatisfactory, the slide can be destained by placing it in xylene to remove the cover slip or immersion oil and then placing it in 50% alcohol for 10 min to hydrate the slide. Destain the slide in 10% acetic acid in water for several hours, and then wash it thoroughly first in water and then in 50 and 70% alcohols. Place the slide in stain for 8 min, and then complete the stain procedures. It is helpful to eliminate or shorten the destain step. 

Vaginal material is best submitted as liquid in a tube, although swabs submitted in a small amount of saline may be used. A drop of the material is covered with a cover slip and examined with reduced light. To culture, 1 or 2 drops of urine sediment or vaginal exudate are inoculated into tubes of warmed, modified Diamond medium. If vaginal swabs are submitted, the swab is immersed in the medium and pressed against the side of the tube to express material. Tubes are incubated at 35°C, and drops of culture are examined by wet mount at 48 and 72 h for motile trophozoites. 

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... 

The kinetics of polymer/polymer demixing are many orders of magnitude slower than those for polymer/solvent demixing. In a typical instrument used to study blend demixing a polymer film supported on a thin glass cover slip is placed in a ther-mostatted pressure cell (Fig. 7.18c). The sample is annealed for some hours well... 

Mount and coverslip Mount slides using clean cover slips and dry overnight. Slides can be cleaned the following day using xylene or chloroform. Remember, it is important to remove all bubbles from under the cover slip. Be conservative with the amount of Permount used in mounting, as using too much can obstruct the view of the sections under a microscope. 

Senkpiel K, Klagge E, Korting HJ. Inhibition of fading in FITC-labelled cover-slip preparations. Acta Histochem 1985 77(2) 159-164. 

Several types of testing were employed to evaluate the bactericidal efficacies of the coated substrates. Five of the coatings on circular glass cover-slips (12 mm diameter) were challenged with the bacterium Staphylococcus aureus (ATCC 6538). This was accomplished by adding a 50- jlL suspension of 10 CFU S. aureus to the surface of each sample. At predetermined contact times a 25- jlL aliquot was removed from the surface, quenched with sterile 0.02 N sodium thiosulfate, and plated on nutrient agar. The viable bacterial colonies were then counted after 48 h incubation at 37°C. Fabric samples were tested by two methods. In one, small squares (1.0-1.5 cm) were placed on a Tryptic Soy agar plate that was inoculated... 

This method is suitable for growing the adherent cells on a cover-slip for microscopy purposes. The simplest step is poly-L-Lysine mobilisation for growing the adherent cells on the slides. 

Poly-L-lysine coated cover slips or the chamber slides... 

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