Phosphotungstic acid-haematoxylin stain
（重定向自Phosphotungstic acid hematoxylin）
_PTAH1754.JPG")
Phosphotungstic acid haematoxylin (PTAH) is a mix of haematoxylin with phosphotungstic acid, used in histology for staining.
It stains some tissue in contrasting colors in a way similar to haematoxylin and eosin stain, as phosphotungstic acid binds to tissue proteins. It is used to show gliosis in the central nervous system, tumours of skeletal muscles, and fibrin deposits in lesions. Muscle is stained blue-black to dark brown, connective tissue is pale orange-pink to brownish red, fibrin and neuroglia stain deep blue, coarse elastic fibers show as purple, and bone and cartilage obtain yellowish to brownish red color.