Trichloroacetic acid is a monocarboxylic acid and an analogue of acetic acid in which three hydrogen atoms of the methyl group have been substituted by chlorine. It is toxic and corrosive to metals and tissue. Trichloroacetic acid is available in different purities and quantities. It can be used in macromolecule precipitation, as a fixative in microscopy, and a reagent in organic synthesis to detect albumin, medicine, or herbicides.