Iron binding capacity

The concentration of transferrin in plasma is approximately 300 mg/dL. This amount of transferrin can bind 300 pg of iron per deciliter, so that this represents the total iron-binding capacity of plasma. However,... 

Determinations of plasma Iron, total Iron-binding capacity (TIBC), and % transferrin saturation... 

Hematological Methods. Hematological analyses can Include the determination of the total hemoglobin concentration (In g%), the packed cell volume (PCV In %), the red blood cell count (In 10 /mm ) and reticulocytes count (In %), calculation of the red cell Indices, examination of a blood film, tests to demonstrate the presence of Inclusion bodies and of sickle cells, tests to evaluate the distribution of fetal hemoglobin (Hb-F) Inside the red cells, the red cell osmotic fragility, the concentration of serum Iron (SI), total Iron binding capacity (TIBC), and the survival time of the red cells. Details of all... 

Yeh, Y-Y., and Zee, P. Mlcromethod for Determining Total Iron-Binding Capacity by Flameless Atomic Absorption Spectrophotometry". Clin. Chem. (1974), 20, 360-364. 

Iron is, as part of several proteins, such as hemoglobin, essential for vertebrates. The element is not available as ion but mostly as the protein ligands transferrin (transport), lactoferrin (milk), and ferritin (storage), and cytochromes (electron transport) (Alexander 1994). Toxicity due to excessive iron absorption caused by genetic abnormalities exists. For the determination of serum Fe a spectrophoto-metric reference procedure exists. Urine Fe can be determined by graphite furnace (GF)-AAS, and tissue iron by GF-AAS and SS-AAS (Alexander 1994 Herber 1994a). Total Iron Binding Capacity is determined by fuUy saturated transferrin with Fe(III), but is nowadays mostly replaced by immunochemical determination of transferrin and ferritin. 

Decreased red blood cell (RBC) count, hemoglobin (Hgb) and hematocrit (Hct) iron metabolism may also be altered [iron level, total iron binding capacity (TIBC), serum ferritin level, and transferrin saturation (TSAT)]. Erythropoietin levels are not routinely monitored and are generally normal to low. Urine positive for albumin or protein. 

Total iron-binding capacity (TIBQ—quantifies the ironbinding capacity of transferrin and is increased in iron-deficiency anemia... 

FIGURE 63-3. The anemia evaluation process. MCV, mean corpuscular volume Pb, lead TIBC, total iron binding capacity ACD, anemia of chronic disease. 

SH Social history TIBC Total iron-binding capacity... 

F, female M, male MCH, mean corpuscular hemoglobin MCHC, mean corpuscular hemoglobin concentration MCV, mean corpuscular volume RBC, red blood cell RDW, red blood cell distribution TIBC, total iron-binding capacity. 

The earliest and most sensitive laboratory change for iron-deficiency anemia is decreased serum ferritin (storage iron), which should be interpreted in conjunction with decreased transferrin saturation and increased total iron-binding capacity (TIBC). Hb, hematocrit, and RBC indices usually remain normal until later stages of iron-deficiency anemia. 

More recent determinations of serum iron have been reported by Schmidt 57), who simply diluted with lanthanum chloride solution, and by Tavenier and Hellen-doorn58), who deproteinized samples in the latter study, iron in the protein precipitate is analyzed to correct the serum iron level. Uny etal. 59) determined serum iron, using ultrasonic nebulization of the sample to increase the sensitivity. Olson and Hamlin 6°) have determined serum iron and total iron-binding capacity. Proteins are precipitated and iron (III) is released by heating with trichloroacetic acid. 

Iron (and/or other related parameters such as ferritin, total iron binding capacity)... 

Brydon and Roberts- added hemolyzed blood to unhemolyzed plasma, analyzed the specimens for a variety of constituents and then compared the values with those in the unhemolyzed plasma (B28). The following procedures were considered unaffected by hemolysis (up to 1 g/100 ml hemoglobin) urea (diacetyl monoxime) carbon dioxide content (phe-nolphthalein complex) iron binding capacity cholesterol (ferric chloride) creatinine (alkaline picrate) uric acid (phosphotungstate reduction) alkaline phosphatase (4-nitrophenyl phosphate) 5 -nucleotidase (adenosine monophosphate-nickel) and tartrate-labile acid phosphatase (phenyl phosphate). In Table 2 are shown those assays where increases were observed. The hemolysis used in these studies was equivalent to that produced by the breakdown of about 15 X 10 erythrocytes. In the bromocresol green albumin method it has been reported that for every 100 mg of hemoglobin/100 ml serum, the apparent albumin concentration is increased by 100 mg/100 ml (D12). Hemolysis releases some amino acids, such as histidine, into the plasma (Alb). 

Modular design. Synthetic molecules were constructed of multiple, closely related nonsymmetric repeat units that can be covalently attached from either end. This approach allows rational design of various congeners, controlling their physical properties, such as iron-binding capacities and partition coefficients (lipophilic/hydrophilic... 

MCV, mean cell volume MCHC, mean cell hemoglobin concentration SI, serum iron TIBC, transferrin iron-binding capacity. 

For patients who are treated chronically with parenteral iron, it is important to monitor iron storage levels to avoid the serious toxicity associated with iron overload. Unlike oral iron therapy, which is subject to the regulatory mechanism provided by the intestinal uptake system, parenteral administration, which bypasses this regulatory system, can deliver more iron than can be safely stored. Iron stores can be estimated on the basis of serum concentrations of ferritin and the transferrin saturation, which is the ratio of the total serum iron concentration to the total iron-binding capacity ( ). 

There is an increase in serum iron and total iron-binding capacity similar to that reported in patients with hepatitis. 

Lactoferrm, found tn mother s milk, appears to be the most potent antibacterial transferrin and seems to play a role in the protection of breast-fed infants from certain infectious diseases. It has been claimed that milk proteins remain intact in the infant s stomach for up to 90 minutes and then pass into the small intestine unchanged, thus retaining their iron-binding capacity. In guinea pigs, addition of hematin to the diet abolishes the protective effects of the mother s milk. 09... 

The binding capacity of serum proteins is altered by oral contraceptives (195) and leads to alterations in the serum concentrations of various substances, including thyroxine, cortisol, and serum iron (196), and in serum iron binding capacity, which are all increased. 

Serum Total Iron and Total Iron Binding Capacity The results for the determination of serum total iron and total iron-binding capacity of rats fed treatment diets for 18 months are also listed in Table VI. A significant increase in serum total iron was detected in rats fed the Maillard browned egg albumin over their control group. Increased serum total iron with normal total iron binding capacity is associated with hemolytic anemia, hemochromatosis, hemosiderosis, and hepatitis (30 ). On the basis of other clinical and histopathological data, however, none of these causes are likely. 

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