Isopropanol is classified as which type of solvent?

• A. Dehydrant
• B. Clearing
• C. Infiltration/embedding
• D. Dehydrant and clearing aka universal solvent

Answer: (A)

Isopropanol is used as a dehydrating solvent in tissue processing. It mixes with water and can replace the water in fixed tissues during the dehydration steps, allowing the tissue to be progressively dried before clearing and embedding. It can be used as an alternative to ethanol in the dehydration series, but it does not serve as a clearing agent—that role is filled by clearing solvents like xylene or limonene-based substitutes. The idea of a universal solvent isn’t applicable here; the appropriate classification for isopropanol in this context is as a dehydrant, since its primary function in the protocol is to remove water from the tissue before clearing and infiltration.