254 INDIUM 



Indium 114 (49 days, 72 sec) Beta 2.05, 0.65 Gamma 0.192-1.27 IT K 



Cat. No. Sp. Act. Form Cost Chem. Cont. Radiochem. Conl. 



In-114-I 70mc/g Metal $51/10 mc — — 



In-114-P 50-150 mc/g Chloride $5/mc — — 



Mica W. Int. C. Scint. C. R//mc 



7.3 X 10-5 74 X 10-5 3.5 X lO'^ 1.4 



Intake Levels, Indium is a rare element and, so far as known, has 

 not been of biological interest. With rats, 5 to 10 mg indium sulfate fed 

 daily for 27 days had no ill effects. However, at 30 mg the animals lost 

 weight. Indium is much more toxic when given parenterally. 



Radioassay. No particular counting problems would be anticipated. 



Chemistry. Indium resembles gallium and aluminum in its behavior. 

 A colorimetric method has been reported for estimation of small amounts 

 (In-1). The procedure is based upon formation of an 8-hydroxyquin- 

 oline derivative which is extracted into chloroform for colorimetric 

 measurement. 



In-1. Moeller, Therald: The Chemistry of Indium, Ind. Eng. Chem. Anal. Ed., 15: 

 270-272 (1943). 



