CLEARING Flashcards
• serves as a bridge between dehydration and infiltration
Clearing
Clearing
• serves as a bridge between _____ and _____
dehydration and infiltration
______ and ______ are immiscible
paraffin wax and ethanol
______ are miscible with both ethanol and paraffin wax
clearing agents
Clearing agent
Xylene
Clearing
many (but not all) clearing agents impart an _____ or _____to the tissue
- high refractive index
optical clarity or transparency
Clearing
• remove substantial amount of____ from tissue
fat
_____presents a barrier to wax infiltration
fat
Clearing
• performed in both:
- embedding process
- mounting tissues
Clearing in
- embedding process
Bridge between dehydration and infiltration
Clearing in - mounting tissues
After staining
To make slide clearer
Choice of
Clearing Agent
• depends on:
- the type of tissue
- type of processing and processor system
- intended processing conditions
• e.g. temperature, vacuum and pressure - safety factors, cost and convenience
Examples of Clearing Agents
Organic Solvents
Oils
Clearing agents
- Xylene
- Benzene
- Toluene
- Terpineol
- Chloroform
- others
Oils
- Cedarwood oil
- Aniline oil
- Clove oil
- Oil of Bergamot
- Oil of oreganum
- lead-free gasolie
Xylene (3) characteristics
• most common
• rapid
• readily miscible with paraffin wax
tissues best cleared from absolute alcohol
Why?
- incomplete dehydration will cause xylene to turn milky