ADHESIVES AND MOUNTING MEDIA Labeling Flashcards
(67 cards)
substances which can be smeared on to the slides so that the sections stick well to the slides.
ADHESIVES
• choice of _ and _ will be influenced by the staining methods to be subsequently applied.
slide and adhesive
adhesives are not necessary for __ provided that the slides are clean and free from grease.
routine staining,
Section can fixed to the slides be done either by
1.
2.
3.
- leaving the slides in a 37°C incubator overnight
- placing the slides in a wax oven at 56° to 60°C for 2 hours
- drying the slides on a hot plate at 45° to 55°C for 30 to 45 minutes
• essential for methods that require exposure of sections to acids and alkalis (especially ___ ) during staining.
Adhesive
- ammoniacal silver solutions
For more delicate tissues like the CNS tissue or brain, a___ is recommended to avoid __
- longer drying time at lower temperature (e.g. 37°C for 24 hours or longer)
- splitting and cracking of the section due to excess heat
Instances when sections may float from the slide and adhesives are necessary:
1
2
3
4
5
• Urgent cryostat sections to be submitted for immunocytochemistry
• Central nervous system tissues
• Tissues containing blood clot
• Tissues which have been decalcified
• When sections are to be subjected to high temperatures
• FORMULA of Mayer’s Egg Albumin
• Egg White 50 cc.
• Glycerin 50 cc.
• most commonly used because it is very easy to make, is convenient, and is relatively inexpensive.
Mayer’s Egg Albumin
• FORMULA of Gelatin (1%)
• Gelatin 1 gm
• Distilled water 100 ml
• Glycerol 15 ml
• Phenol Crystal 2 gm
• Adding up to __ to the _ in a floating out bath and mixing it well is a most convenient alternative to direct coating of slides.
Gelatin (1%)
- 30 ml of 1% aqueous gelatin to the water
• FORMULA of Gelatin-formaldehyde mixture
• Coat the slides with the above mixture. Allow coated slides to dry at _ for __ before use.
• 1% gelatin 5 ml
• 2% formaldehyde 5 ml
- 37°C for one hour or overnight
• This is widely used as a section adhesive in immunohistochemistry.
Poly-L-Lysine
• This aqueous detergent can be purchased as a 0.1% solution which is further diluted 1:10 with distilled water (final dilution to __ ) prior to use.
Poly-L-Lysine
- 0.01%
are very useful in cytology, particularly for cytospin preparations of proteinaceous or bloody material.
APES (3-aminopropylthriethoxysilane)
are better than poly-L-lysine coated slides because they can be stored for a long time without losing their adhesiveness.
APES (3-aminopropylthriethoxysilane)
last step in tissue processing that results in a permanent histological preparation suitable for microscopy, after adhesion of the sections on to the slide and appropriate staining of the tissue.
Mounting
usually a syrupy fluid applied between the section and the coverslip after staining, for __ and __
MOUNTING MEDIUM
- setting the section firmly
- preventing the movement of the coverslip
MOUNTING MEDIUM purpose
- protects the stained section from getting scratched
- to facilitate easy handling and storage of the slides
- to prevent bleaching or deterioration due to oxidation, thereby preserving the slides for permanent keeping.
• often chosen for a specific refractive index (R.I.), which can enhance specimen details or make them invisible.
MOUNTING MEDIUM
is important because it governs the contrast between the cellular detail and the background, and also the transparency of the observed sample against the bright field of the microscope.
Refractive index
The mounting media must always have ___ the mounted sample to impart more transparency.
Refractive index higher than
Characteristics of a good mounting medium: (10)
- It should be colorless and transparent.
- It should be freely miscible with xylene and toluene.
- It should not dry to a non-stick consistency and harden relatively quickly.
- It should protect the section from physical damage and chemical activity (oxidation and changes in pH).
- It should be resistant to contamination (particularly microorganism growth).
- It should not cause shrinkage and distortion of tissues. 7. It should not leach out any stain or affect staining.
- It should not change in color or pH.
- It should be compatible with the adhesive in use.
- It should set without crystallizing, cracking or shrinking (or otherwise deform the tissue being mounted) and not react with, leach or induce fading in stains and reaction products (including those from enzyme histochemical, hybridization, and immunohistochemical procedures).
• Slides should be properly labeled with an __ on the side of the mounted coverslip to.
Labeling
- identifying case number
