Rapid determination of trace amounts of selenium in biological samples by gas chromatography with electron-capture detection

A rapid, simple and sensitive method of determining total selenium in biological samples is described. Selenium(IV) reacts with 1,2-diamino-3,5-dibromobenzene to form 4,6-dibromopiazselenol, which is detected by means of a gas chromatograph equipped with an electron-capture detector. In order to complete the mineralisation of selenium in seven organic compounds, a wet digestion method was employed. Thirty determinations can be made in 8 h by a modified method. Trace amounts of total selenium in NBS standard reference materials, human blood and serum were determined and compared with the certified or reported values.