Speciation of astatine reacted with oxidizing and reducing reagents by thin layer chromatography. Formation of volatile astatine

Radio-chromatography was conducted by using the astatine radionuclides ^209,210,211At produced in the ⁷Li induced reaction of ²⁰⁹Bi. The speciation of dissolved astatine chemical species of astatide (At^-), astatate (AtO₃^-) and perastatate (AtO₄^-) was carried out by thin layer chromatography on silica gel with an ethanol/water solution. Amounts of the astatine species varied with concentrations of oxidizing and reducing reagents, potassium periodate, sodium sulfate and hydrazine hydrate. The oxidation-reduction reactions between At^-(-I) and AtO₃^- (V) were found to form volatile At⁰ (0) and release it from a silica gel thin layer in the development. (author)