toluidine blue O

to·lu·i·dine blue O

[C.I. 52040]
a blue basic dye, used as an antibacterial agent, as a nuclear stain, and to stain metachromatically certain structures (for example, the granules in mast cells; cartilage matrix that is rich in chondroitin sulfate), and in electrophoresis to stain RNA, RNase, and mucopolysaccharides; it also antagonizes the anticoagulant action of heparin.
See also: tolonium chloride.
References in periodicals archive ?
The two most useful stains can be purchased ready-to-use from Carolina Biological: toluidine blue O (available as a 1% aqueous solution) and Lugol's solution ([I.