【摘要】 本文研究了新的催化显色反应测定痕量硒.方法是在pH2.4的磷酸—磷酸二氢钾介质中,硒（Ⅳ）催化氯酸钾氧化对溴苯肼生成偶氮离子,继而与H-酸偶合成红色的偶氮染料.在一定的硒（Ⅳ）浓度范围内,红色偶氮化合物在520nm处的吸光度与硒（Ⅳ）的量成正比.其线性范围为1.2～12ng/ml,表观摩尔吸光系数达3.65×10⁶L·mol^-1·cm^-1,已满意地用于人发样品中痕量硒的测定,并证实癌症病人发样中的硒含量明显低于正常人.更多还原

【Abstract】 In this paper, a new catalytic colour-developing reation for determination of trace Selenium has been studied.Selenium catalyzes the oxidation of p-bromopheny hydrazine by KClO3 to diazo ion, which then is converted to a red azo dye by coupling with H-acid.The reaction is proceeded in H3PO4-NaH2PO4 buffer medium of pH 2.4 and at boiling water bath, which can be inhibited with running cold water easily. The absorption maximum of the red azo dye occurs at 520nm, The calibration graph is linear in the range 1.2-12 ng/ml Selenium. The sensitivity of this method presented as apparent molar absorptivity is 3.65×106L·mol-1·cm-1.This method has been applied satisfactorily for the determination of trace Selenium in human hair and proves that the hair Selenium content of cancerous man is obviously lower than that of healthy man.更多还原