Organic and inorganic selenium speciation using high-performance liquid chromatography with UV irradiation and hydride generation-quartz cell atomic absorption spectrometric detection

We propose a new on-line method for organic and inorganic selenium speciation, consisting of liquid chromatography-UV irradiation-hydride generation-quartz cell atomic absorption spectrometry. Unlike other methods, UV irradiation for the derivatization of all selenium species to selenite, before hydride generation, is a simpler and cleaner method, since it does not require any additional reagent. The reaction time is also much shorter. A good resolution between the four species (selenite, selenate, selenocystine and selenomethionine) is achieved in less than 15 min. The optimisation of operating conditions, including those used during separation and UV irradiation, is described. Detection Limits, precision, linear ranges and recovery are reported. The technique can be considered a reliable, straightforward system for selenium speciation. (C) 1998 Elsevier Science B.V. All rights reserved.