6-MOUNTING Flashcards
What is an adhesive in histology
A substance smeared on slides so sections stick well
Why are adhesives essential in some staining methods
For methods exposing sections to acids/alkalis
Give examples of when sections may float from the slide
Urgent cryostat sections for immunocytochemistry; CNS tissues; tissues with blood clot; decalcified tissues; sections exposed to high temperatures
List six examples of adhesives used in histology
Mayer’s Egg Albumin; Dried albumin; Gelatin (1%); Gelatin-formaldehyde mixture; Poly-L-Lysine; APES (3-aminopropylthriethoxysilane)
What is Mayer’s Egg Albumin composed of
Equal parts glycerin
What is the most commonly used adhesive
Mayer’s Egg Albumin
What is a disadvantage of Mayer’s Egg Albumin
Retains some stain and gives a dirty background
What does a mounting medium do
Bonds specimen
What properties should a mounting medium have
Transparent with an index of refraction close to glass and tissue
What is the purpose of mounting medium
Preserves slides for permanent keeping; prevents distortion of image during microscopic examination
List eight characteristics of a good mounting medium
Colorless and transparent; freely miscible with xylene and toluene; should not dry to a non-stick consistency; harden relatively quickly; protect from physical damage/chemical activity; resistant to contamination; should not cause shrinkage/distortion; should not leach stain or affect staining
List seven more characteristics of a good mounting medium
Should not change in color/pH; compatible with the adhesive in use; should set without crystallizing
What are the two main types of mounting media
Aqueous and Resinous
List five examples of aqueous mounting media
Water; Glycerin; Farrant’s Medium; Apathy’s Medium; Brun’s Fluid
List four examples of resinous mounting media
Canada Balsam; DPX (Dibutyl Phthalate and Xylene); XAM; Clarite
What is the refractive index of Canada Balsam
RI 1.524
From what is Canada Balsam extracted
The Canadian tree
Describe Canada Balsam
Transparent
What is coverslipping
Covering the section with a thin piece of plastic or glass
What is the purpose of coverslipping
Protects the tissue from being scratched; provides better optical quality
What is ringing
Sealing the margins of the coverslip
What are the purposes of ringing
Prevent the escape of fluid or semi-fluid mounts/evaporation; fix the coverslip in place; prevent sticking of slides upon storage
