“…For the detection of alkali metal ions, tetracyanoquinodimethanide may be applied (396); use of violuric acid requires especially purified silica gel (HOI). TLC is now beginning to be used for the diagnosis of heavy metal poisoning (889) and in the separation of organometallie compounds (217,1366) and phosphoric acid esters (828). Its application to inorganic anions has also been started (1398,1400).…”