Colloid iodine

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

According to J. Amann,7 brown soln. of iodine contain ultra-microscopic particles, while the violet soln. contain none. The violet-red soln. in benzene, toluene, and xylene are photosensitive in that clouds of ultramicroscopic particles are formed in white light, and the soln. rapidly turn brown. The soln. return to their original state in darkness. In some cases, iodine soln. are true soln. either of free iodine or of an addition compound and in other cases they contain free colloidal iodine or of a polymerized addition compound. In some cases ultra-microscopic suspended particles of iodine are present. 

Actomar AI3-08544 Caswell No, 501 Diiodine EINECS 231-442-4 EPA Pesticide Chemical Code 046905 Eranol Ethanolio solution of iodine HSDB 34 lODE Iodine iodine (resublimed) Iodine-127 Iodine colloidal Iodine crystals Iodine solution Iodine sublimed Iodine Tincture DSP lodio losan superdip Jod Jood Molecular Iodine NSC 42355 Tincture iodine Vistarin. Nonmetallic halogen element dyes, alkylation and condensation catalyst, iodides, iodates, antiseptics, germicides, x-ray contrast media, food and feed additive, stabilizers, photographic film, water treatment,... 

Some unsaturated compounds are capable of quantitative hydrogenation in a solution of colloidal palladium. It has been found that a hydrogen number corresponding to the iodine number of fatty oils may be ascribed to some ethereal oils. 

Brom-jod, n. iodine bromide, -kalium, n. potassium bromide, -kalzium, n., kalk, tn. calcium bromide, -kampher, tn. bromo-camphor, Pharm.) monobromated camphor, -kohlenstoff, tn. carbon (tetra)bromide. -korper, tn. Colloids) "bromide body (bromide ion), -kupfer, n. copper bromide, lauge, /. bromine lye (solution of sodium hypobromite and bromide made by passing bromine into sodium hydroxide solution), -lithium, n. lithium bromide. -Idsung, /. bro-nune solution, -magnesium, n. magnesium bromide. -metall, n. metallic bromide. 

The formation of triiodothyronine (T3) and tetra-iodothyronine (thyroxine T4) (see Figure 42—2) illustrates many of the principles of diversity discussed in this chapter. These hormones require a rare element (iodine) for bioactivity they are synthesized as part of a very large precursor molecule (thyroglobuhn) they are stored in an intracellular reservoir (colloid) and there is peripheral conversion of T4 to T3, which is a much more active hormone. 

The amounts oi adsorption of the polymer on latex and silica particles were measured as follows. Three milliliters of the polymer solution containing a known concentration was introduced into an adsorption tube(lO ml volume) which contained 2 ml of latex (C = l+.O wt %) and silica(C = 2.0 wt %) suspensions. After being rotated(l0 rpm) end-over-end for 1 hr in a water bath at a constant temperature, the colloid particles were separated from the solution by centrifugation(25000 G, 30 min.) under a controlled temperature. The polymer concentration that remained in the supernatant was measured colorimetrically, using sulfuric acid and phenol for the cellulose derivatives(12), and potassium iodide, iodine and boric acid for PVA(13). From these measurements, the number of milligrams of adsorbed polymer per square meter of the adsorbent surface was calculated using a calibration curve. 

Although the dipolar and resonating nature of the interaction of amylose and iodine is well established, Schlamowitz173 regards the iodine in a starch complex as being in a predominantly non-polar form, and Meyer and Bern-feld174 refute the helix theory and consider that adsorption of iodine occurs on colloidal micelles in amylose solutions. Most of the experimental facts which Meyer presents can, however, be satisfactorily explained on the helical model. 

Iodine, most ancient of the therapeutic agents for thyroid disorders, inhibits the secretion of thyroid hormone by retarding both the pinocyto-sis of colloid and proteolysis. This effect is observed in euthyroid as well as hyper thyroid persons. 

Triiodothyronine is not classified as a thyroid inhibitor it is an amino acid derivative of thyronine and results from the oxidative coupling of monoiodotyrosyl and diiodotyrosyl residues. Iodine 131, the most often used radioisotope of I, is rapidly absorbed by the thyroid and is deposited in follicular colloid. Prom the site of its deposition, Bll causes fibrosis of the thyroid subsequent to pyknosis and necrosis of the follicular cells. 

As indicator enzymes horseradish peroxidase (HRP or HRPO), alkaline phosphatase (AP), or /i-galactosidase, are favored, since they are relatively robust, have a high product-forming rate, are easy to purify, and are cheap. The most used colloids are from gold, silver, and iron, and iodine isotopes are mostly taken as radioactive labels in immunoassays. 

Thyroid epithelial cells synthesize and secrete T4 and T3 and make up the functional units of thyroid glandular tissue, the thyroid follicles. Thyroid follicles are hollow vesicles formed by a single layer of epithelial cells that are filled with colloid. T4,T3, and iodine are stored in the follicular colloid. T4 and T3 are derived from tyrosyl residues of the protein thyroglobulin (Tg). Thyroid follicular cells synthesize and secrete Tg into the follicular lumen. Thyroid follicular cells also remove iodide (I ) from the blood and concentrate it within the follicular lumen. Within the follicles, some of the tyrosyl residues of Tg are iodinated, and a few specific pairs of iodoty-rosyl residues may be coupled to form T4 and T3. Thus, T4, T3, and iodine (in the form of iodinated tyrosyl residues) are found within the peptide structure of the Tg that is stored in the follicular lumen. 

T4, T3, MIT, and DIT are stored outside the cell in the follicular colloid in peptide linkage within the Tg molecules. In normal humans on an iodine-sufficient diet, Tg makes up approximately 30% of the mass of the thyroid gland and represents a 2- to 3-month supply of hormone. The total amount of iodine contained as T4, T3, MIT, and DIT within Tg varies with the dietary iodine intake. 

Matsuoka, H. and he, N. Small-Angle and Ultra-Small Angle Scattering Study of the Ordered Structure in Polyelectrolyte Solutions and Colloidal Dispersions. Vol. 114, pp. 187-232. Miyasaka, K PVA-Iodine Complexes Formation, Structure and Properties. Vol. 108, pp. 91-130. 

Sulphammonium decomposes into ammonia and sulphur under ordinary pressures. With liquid ammonia in sealed tubes at temperatures between 0° C. and 20° C. it gives the compound (NH3)2S.2NH3, and at —23° C. it forms (NH3)2S.NHa. With iodine in solution in liquid ammonia, sulphammonium forms an ammoniacal compound of sulphur iodide. The blue colour of a solution of sulphammonium may possibly be due to the presence of colloidal sulphur.3... 

A colorimetric method 3 for the detection and estimation of small quantities of selenious acid, which is sensitive to 0-002 per cent., may be carried out as follows Into two cylinders are put, respectively, 5 c.c. of the solution to be tested and 5 c.c. of a solution of selenious acid of approximately the same strength. 70 c.c. of water are added to each and also a drop of gum arabic then 5 c.c. of 5 per cent, hydrochloric acid solution and the whole diluted to 99 c.c. 1 c.c. of a solution of potassium iodide is added to each tube and the contents vigorously stirred. The respective colorations (due to iodine and colloidal selenium) are compared after five minutes in a Ivriiss colorimeter. 

The distillation is continued till the greater part of the liquid has distilled over, and no oily drops are to be seen in the condenser. The residue consisting of a concentrated solution of phosphorus and phosphoric acids in addition to excess of red phosphorus is discarded. The distillate is shaken up with water to remove alcohol, and then with dilute caustic soda to remove free iodine. Enough alkali must be used to render the lower layer of alkyl halide colourless. The latter is then separated ofl, dried over granular calcium chloride (6 gms.) and distilled. The preparation should be kept in the dark in a well-stoppered bottle. If exposed to light, iodine slowly separates, but may be prevented from so doing by adding a small quantity of colloidal silver to the liquid. 

Nitrostarch gives no color with iodine. It is insoluble in water and does not gelatinize to form a paste as starch does when it is boiled with water. It is not notably hygroscopic, but may take Up 1 or 2% of moisture from a damp atmosphere. It is soluble in acetone. The varieties of nitrostarch which are soluble in ether-alcohol contain about the same amounts of nitrogen as the varieties of nitrocellulose which dissolve in that mixed solvent. Nitrostarch does not form a good film or tough colloid as nitrocellulose does. 

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