Haemin (Chlorohemin)
Definition
The oxidised, halide-salt form of haem produced in the Teichmann test. Haemin crystals are brown, rhomboid, and form in pairs or groups under the microscope.
Related terms
- Confirmatory Test
- A test with sufficient specificity to establish the identity of a biological fluid for reporting purposes. Examples include Takayama and Teichmann crystal...
- Glacial Acetic Acid
- Concentrated acetic acid (near 100%), used in the Teichmann reagent to provide an acidic medium that helps oxidise haem and incorporate the...
- Haemochromogen
- A reduced haem-nitrogenous-base complex. In the Takayama test, pyridine is the base, giving pyridine haemochromogen: pink, feathery or needle-like crystals.
- Pyridine
- An aromatic nitrogen heterocycle used as a secondary denaturant in Indian denatured spirit formulations (at 1-2% v/v). Its presence in a headspace...
- Sensitivity Limit
- The minimum amount of blood (or age/dilution of stain) at which the crystal test can still produce identifiable crystals. Below this threshold...
Explained in
- Teichmann and Takayama Crystal TestsThe oxidised, halide-salt form of haem produced in the Teichmann test. Haemin crystals are brown, rhomboid, and form in pairs or groups under the microscope.