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THE EFFECT OF CYANIDE AND OF VARIATION IN ALKALINITY ON THE OXIDATION-REDUCTION POTENTIAL OF THE
1Departments of Physiology of the University of Chicago and The Chicago Medical School.
The Journal of General Physiology
|October 30, 2009
Summary
Cyanide and hydroxyl ions reduce methemoglobin
Area of Science:
- Biochemistry
- Electrochemistry
Background:
- Methemoglobin is an oxidized form of hemoglobin.
- Understanding methemoglobin's interactions is crucial for blood chemistry.
- Oxidant activity of methemoglobin needs further investigation.
Purpose of the Study:
- To investigate the influence of cyanide and hydroxyl ions on methemoglobin.
- To determine the binding sites and effects of these ions on methemoglobin's activity.
- To elucidate the nature of cyanmethemoglobin and alkaline methemoglobin.
Main Methods:
- Potentiometric method was employed.
- Oxidation-reduction potential of the methemoglobin-hemoglobin system was measured.
- Effects of varying pH and cyanide concentration were analyzed.
Main Results:
- Cyanide and hydroxyl ions bind to the iron in methemoglobin.
- This binding reduces the oxidant activity of methemoglobin.
- Cyanmethemoglobin and alkaline methemoglobin are identified as undissociated ferric compounds.
Conclusions:
- Cyanide and hydroxyl ions act as ligands for methemoglobin's iron.
- The interactions form stable ferric compounds, altering redox properties.
- Proposed electronic formulas explain the observed electrical properties of these hemoglobin derivatives.
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