Haem group
Definition
The iron-porphyrin prosthetic group at the centre of haemoglobin. The iron atom cycles between oxidation states during the peroxidase-like reaction, and it is this cycling that catalyses the indicator oxidation.
Related terms
- Confirmatory test
- A species- or analyte-specific test that provides the level of certainty required for a scientific report and court evidence. Immunochromatographic strips targeting...
- False positive
- A test result indicating diatoms consistent with ante-mortem aspiration in an organ sample when the diatoms actually arrived by contamination, post-mortem diffusion,...
- Leuco-phenolphthalein
- The reduced, colourless form of phenolphthalein used in the Kastle-Meyer reagent. It is oxidised back to the pink quinone form in the...
- Peroxidase-like activity
- The catalytic behaviour of haemoglobin (and other haem-containing proteins) that mimics the enzyme peroxidase: splitting hydrogen peroxide into water and oxygen. The...
- Presumptive test
- A fast, low-cost, class-specific screen used to triage a caseload before instrumental work begins. Examples are Marquis reagent for opioids and amphetamines,...
Explained in
- Kastle-Meyer TestThe iron-porphyrin prosthetic group at the centre of haemoglobin. The iron atom cycles between oxidation states during the peroxidase-like reaction, and it is...