Sodium, colloidal iodide

Iodine (Lugol s solution 5% iodine in 10% Kl Sodium and potassium iodide Organic iodide Colloid iodine 10% solution)... 

L. Berczeller has shown that the presence of acids, chlorides, bromides, iodides, thiocyanates, and morphine accelerate the reaction while the presence of tartrates, sulphates, oxalates, carbonates, mercuric chloride, bromide, iodide, and cyanide, most alkaloids, colloids, proteins, etc., inhibit the reaction. Hydrocyanic acid, unlike other acids, also inhibits the reaction. A. Skrabal has shown that Landolt s reaction has a temp, coeff. greater than unity, so that the velocity of the reaction increases with a rise of temp. but if the system contains an excess of sodium sulphate, the temp, coeff. is less than unity, and the velocity of the reaction decreases with a rise of temp. 

Mix equal amounts of 0.020 mol din sodium bromide solution and 0.018 mol dm silver nitrate solution. A colloidal dispersion of silver bromide is formed immediately. A silver iodide sol maybe prepared in a similar manner. 

The expression of the sodium iodide symporter is perhaps nowhere more important than in the thyroid gland. A complete review of the physiological importance of the thyroid is beyond the scope of this chapter. It is sufficient to say that the symporter provides the iodine needed for normal thyroid function. Once the symporter has been trafficked to the basolateral surface of the thyrocyte, it can transport iodine from the blood into the cell. Once inside the cells, iodine is transported to the apical membrane where it is organified through attachment to a tyrosine residue and incorporated into the thyroid hormone thyroglobulin. The thyroglobu-lin is then stored inside thyroid follicles as colloid, to be released into the bloodstream as thyroid hormones (thyroxine and triiodothyronine) via TSH stimulation. 

Fig. 5. Spatial iso-density plots of iodide (white) and fluoride (grey) around a spherical bio-colloid with cationic surfece patches (black spheres). Results from MD simulations in explicit solvent (SPC/E) and a mixture of sodium iodide and fluoride. ...

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