Thionine, also known as thionine acetate or Lauth's violet, is a strongly staining metachromatic dye that are widely used for biological staining. Thionine can also be used in place of Schiff reagent in quantitative Feulgen stain

Feulgen stain

Feulgen stain is a staining technique discovered by Robert Feulgen and used in histology to identify chromosomal material or DNA in cell specimens. It depends on acid hydrolysis of DNA, therefore fixating agents using strong acids should be avoided....

ing of DNA. It can also be used to mediate electron transfer in microbial fuel cell

Microbial fuel cell

A microbial fuel cell or biological fuel cell is a bio-electrochemical system that drives a current by mimicking bacterial interactions found in nature....

s. The dye's name is frequently mis-spelled, with omission of the e. The -ine ending indicates that the compound is an amine

Amine

Amines are organic compounds and functional groups that contain a basic nitrogen atom with a lone pair. Amines are derivatives of ammonia, wherein one or more hydrogen atoms have been replaced by a substituent such as an alkyl or aryl group. Important amines include amino acids, biogenic amines,...

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