Detection of goitrin and its heptafluorobutyryl derivative by gas-liquid chromatography with electron capture, electrolytic conductivity and sulfur detectors.

The separation of goitrin by two gas-liquid chromatographic columns, the response of different detectors and the use of the heptafluorobutyric (HFB) anhydride derivative of goitrin to improve sensitivity was investigated. The non-polar 3% OV-1 and the intermediate 4% SE-30/6% SP-2401 on 80-100 mesh Chromosorb W HP gave comparable results and were considered interchangeable. The sensitivities of the electron capture, sulfur 394 nm emission, chlorine and nitrogen Coulson electrolytic conductivity detectors were inadequate for goitrin per se. Chromatography and sensitivity of all detectors to goitrin were greatly improved by using by using the HFB derivative. It was possible to detect 1 to 60 ng of goitrin-HFB in standard solutions. Application of the technique to goitrin-spiked (2 ppm) milk, cleaned up by high-performance liquid chromatography, encountered no problems and was considered satisfactory for all four detectors.