to remove fixative and water from the tissue and replacing them with dehydrating fluid in preparation for impregnation.

all the aqueous tissue fluids are removed but with little disruption to the tissue due to diffusion currents.

Ratio of Dehydrating Agent to tissue

Ratio of Fixative to tissue

MOST COMMON

for routine dehydration of tissues. BEST DEHYDRATING AGENT

employed for blood and tissue films. can cause blindness (optic blindness)

utilized in plant & animal micro techniques

ethanol + small amount of methanol, used in the same way as ethanol

many of the processing methods for use in a microwave oven recommend this agent.

BOTH fixative and dehydrating agent. Organ for acetone: Brain or CNS. Rapid but penetrates poorly

BOTH dehydrating and clearing agent. Advantage: excellent dehydrating and clearing agent.Tissues can be left for long periods of time without affecting the staining properties of the specimen

BOTH dehydrating and clearing agent. Fast dehydrating

BOTH dehydrating agent and clearing agent. Toxic when ingested or inhaled

Used to dehydrate smears producing minimal shrinkage

acts as a tissue softener for hard tissues such as tendons, nails, or dense fibrous tissues.

can act as BOTH dehydrating agent and an indicator of water content of the last bath (100% ETOH). BLUE indicates presence of water. serves as an indicator that dehydration is complete (white blue)

MOST COMMONLY USED in routine procedures. Colorless clearing agent

Substitute for xylene or benzene. Also used both for embedding and mounting process

Recommended for URGENT BIOPSIES

Slower in action. May cause HEPATOTOXICITY

Recommended for CNS TISSUE AND CYTOLOGY. Very expensive

Recommended for embryos, insects, and VERY DELICATE TISSUES

Causes MINIMUM SHRINKAGE. Becomes adulterated

Similar to chloroform but cheaper. Highly toxic upon prolonged exposure

Slow acting. For double embedding techniques

No dealcoholization but make the tissues clearer