Hemoglobin in water

The sedimentation coefficient of a sample of human hemoglobin in water is equal to 4.48 svedberg at 20°C, and its density is 1.335 g mL . The density of water at this temperature is equal to 0.998 g mL . Use the value of the diffusion coefficient from Example 10.16 to determine the molar mass of hemoglobin. 

Most nitrites are soluble in water and mildly toxic. Despite their toxicity, nitrites are used in the processing of meat products because they retard bacterial growth and form a pink complex with hemoglobin that inhibits the oxidation of blood (a reaction that would otherwise turn the meat brown). Nitrites are responsible for the pink color of ham, sausages, and other cured meat. 

Early determinations of iron and hemoglobin in blood were described by Herrmann et al53) and Bohmer et al 54). Zettner and co-workers ss) determinent serum iron by extracting the bathophenanthroline complex into MIBK. The serum could be diluted with water and aspirated only if the iron level was above 2 ppm. Rodgerson and Heifer S6) tried aspirating undiluted serum but obtained irreproduc-... 

One approach to compartmentalize hemoglobin is to encapsulate hemoglobin in biodegradable polymer-PEG-polylactide (30). These nanocapsules have a diameter of 80-150 nm and contain superoxide dismutase, catalase, carbonic anhydrase, and other enzymes of Embden-Meyerhof pathway that are needed for long-term function of an oxygen carrier (31,32). The polylactide capsules are metabolized in vivo to water and carbon... 

Nitrate in drinking water above the standard poses an immediate threat to children under three months of age. In some infants, excessive levels of nitrate have been known to react with the hemoglobin in the blood to produce an anemic condition commonly known as blue baby. If the drinking water contains an excessive amount of nitrate, it should not be given to infants under three months of age and should not to be used to prepare formula. The standard allows for 10.0 mg of nitrate (as N) per liter of water. Nitrate can be removed from water by ion exchange, RO, or distillation [48]. 

The most important task of the red blood cells (erythrocytes) is to transport molecular oxygen (O2) from the lungs into the tissues, and carbon dioxide (CO2) from the tissues back into the lungs. To achieve this, the higher organisms require a special transport system, since O2 is poorly soluble in water. For example, only around 3.2 mb O2 is soluble in 1 L blood plasma. By contrast, the protein hemoglobin (Hb), contained in the erythrocytes, can bind a maximum of 220 mb O2 per liter—70 times the physically soluble amount. 

Hematological Effects. A transient increase in blood reticulocytes was observed in workers exposed to niekel in water from a contaminated water fountain (Sunderman et al. 1988). The water was also eontaminated with boric acid, and the contribution of boric acid to this effect is not known. Inconsistent effeets on hematoerit values were found in rats following inhalation exposure (Weiseher et al. 1980). A reversible deerease in hemoglobin and increases in leukocyte counts were observed in rats after oral exposure to niekel (American Biogenics Corporation 1988 Whanger 1973). Intrarenal injection of nickel subsulfide in animals resulted in erythrocytosis (Hopfer and Sunderman 1978 Hopfer et al. 

Figure 2.9 is a plot of possible combinations of hydration and asymmetry for protein particles in water. Similar curves could be drawn for other materials as well. For the human hemoglobin molecule discussed in Table 2.1, the combination of sedimentation and diffusion measurements gives an /// value that lies within the domain defined by the 1.15 and 1.20 contours of Figure 2.9. The current picture of the structure of human hemoglobin, deduced from x-ray diffraction studies, suggests that the molecule may be regarded as an ellipsoid with height, width, and depth equal to 6.4, 5.5, and 5.0 nm, respectively. Applying these dimensions to the dispersed unit leads us to describe the particle as being hydrated to the extent of about 0.4-0.5 g water (g protein)...

Hemolysis is the leakage of hemoglobin into liquid such as plasma, and is due to disruption of the erythrocytes. Within the body, hemolysis maybe caused by some diseases or poisons, whereas hemolysis outside the body, as in artificial organs, is caused by physical or chemical factors. If erythrocytes are placed in water, hemolysis will occur as the cells rupture due to the difference in osmotic pressure between water and the intracellular liquid. Hemolysis in artificial organs and their accessories occurs due to a variety of physical factors, including turbulence, shear, and changes of pressure and velocity. It is difficult, however, to obtain any quantitative correlation between the rates of hemolysis and such physical factors. 

Saponins consist of a terpenoid core (the aglycone), having oxygenated positions bound to sugar moieties (up to ten monosaccharidic units). In water they form colloidal solutions which foam on shaking and precipitate cholesterol. When saponins are near cell membranes, their interaction with cholesterol may create pore-like structures that eventually cause the membrane to burst. Hemolysis is an example of this phenomenon (i.e. the distraction of erythocyte membranes, but not hemoglobin). Occasionally, they cause hypersecretion, which could explain their expectorant activities and also their toxicity to fish. 

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