embedding Flashcards
Done after wax impregnation
Embedding
Positioning the tissue in the mold; generally the surface of the section to be cut should be parallel to the bottom of the mold
Orientation
Tubular structures (arteries, fallopian tubes) cut in
x-section of the lumen
Skin, intestine, gall bladder, and other epithelial biopsies cut in
a plane at right angles to the surface
Muscle biopsies cut in
transverse longitudinal planes
2 L-shaped strips of heavy brass or metal; size of mold is adjustable
Leuckhart’s embedding mold
multiple compartments or grids for multiple embedding
Compound embedding unit
stainless steel base mold with plastic embedding ring, e.g., Tissue Tek
Plastic embedding rings and base molds
peel away (3 sizes; 22x22mm, 22x30mm, 22x40mm), ice tray, paper boat (no need for trimming)
Disposable molds
used for fragmentary biopsies
Watch glasses
Tissue processing and embedding system composed of 3 pieces: perforated bottom, frame center piece, and perforating lid
TIMS
Advantage of TIMS
fixation, dehydration, clearing, and embedding
Embedding medium used for hard tissues and large sections of whole organs
Celloidin or Nitrocellulose method
Double infiltration technique: first with celloidin, then embedded with paraffin
Double embedding method
Embedding technique for electron microscopy to allow tissue sectioning of 80nm thickness
Plastic resin embedding
Embedding method used for high-resolution light microscopy and renal biopsies (tissue section of 2mm)
Plastic resin embedding
Embedding method suitable for extremely hard tissues
Plastic resin embedding
Embedding medium with the widest application for both light and electron microscopy, capable of producing sections of 30-40nm thickness, preferred for TEM
Epoxy
Most stable epoxy resin, slow acting, used for electron microscopy embedding
Bisphenol A (Araldite)
Epoxy resin, less stable but useful, commonly used for embedding
Glycerol (EPON)
Epoxy resin that infiltrates the fastest but is highly toxic
Cyclohexene dioxide (Spurr)
Seldom used, applied in electron microscopy
Polyester
Preferred embedding medium for high-resolution light microscopy
Acrylic plastics
Ideal embedding medium for undecalcified bone, an example of methacrylate
Methyl methacrylate (acrylates)
Used for TEM, involves the use of polyglycol methacrylate and glycerol methacrylate
Methacrylates
