Colloidal indium complex

The distribution and excretion of indium in animals depends greatly on the chemical composition of the indium compound, as well as the route of administration. For example, indium citrate was administered to animals by several routes such as subcutaneous, intramuscular, and intravenous injection (Browning 1969). For subcutaneous injection, the distribution was more uniform, but for intravenous injection, the concentration of indium was highest in the kidneys and liver. Ionic forms of indium are mostly accumulated by the kidney and excreted via the urine, while colloidal indium complexes accumulate in the liver and reticuloendothelial system and are eliminated primarily through the feces (Castro-novo and Wagner 1971). 

Hamada, S., Kudo, Y, and Kobayashi, T., Precipitation of uniform indium hydroxide particles from indium 2-aminobutyrato complex solutions. Colloids Surf. A, 79, 227, 1993. 

Sulfur forms three binary compounds with indium, In2S, InS, and In2S3. The latter is prepared by direct union of the elements, by heating ln208 with sulfur or H2S or by passing H2S into the weakly acid solution of an indium salt. The precipitated form is yellow, and the salt formed by dry methods varies from yellow to brown. It is soluble in mineral acids, readily forms colloidal solutions, and gives complex salts with the alkali sulfides, such as K2In2S . 

Morin, the coloring matter of fustic, is 3,5,7,2, 4 -pentahydroxy flavone (I). Its alcohol solutions react with aluminum salts in neutral or acetic acid solution to give an intense green fluorescence in daylight and ultraviolet light. The fluorescence is due to the formation of a colloidally dispersed inner complex aluminum salt of morin with the probable structure (II), or to an adsorption compound of morin with alumina. Beryllium, indium, gallium, thorium and scandium salts also form fluorescent compounds with morin. The pH of the system has much influence in these reactions. The only metal ion whose reaction with morin is independent of pH is Zr+ or its hydrolysis product (compare page 519). 

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