Methemoglobin

{
  "id": "MLC-T-CHM-007274",
  "term": "Methemoglobin",
  "field": "Chemistry",
  "definition": "A form of hemoglobin containing iron in the ferric (Fe³⁺) oxidation state, rather than the normal ferrous (Fe²⁺) state. This oxidized condition prevents the molecule from binding to oxygen, thereby impairing its capacity for oxygen transport in the blood. Normal physiological levels are typically below 1% of total hemoglobin; elevated concentrations result in methemoglobinemia, a condition causing cyanosis.",
  "synonyms": [
    "methaemoglobin"
  ],
  "subject": "Chemistry and Human Health",
  "references": [
    "PAC, 2007, 79, 1153. 'Glossary of terms used in toxicology, 2nd edition (IUPAC Recommendations 2007)' on page 1260 (https://doi.org/10.1351/pac200779071153)"
  ],
  "url": "https://mlchart.com/terminology/chemistry/methemoglobin/"
}