在ｐＨ３．１～５．２的ＨＣｌ－ＮａＡｃ缓冲介质中，溶液中的铁（Ⅲ）与过氧化氢（Ｈ２Ｏ２），水杨基荧光酮（ＳＡＦ）和溴化十六烷基三甲铵（ＣＦＭＡＢ）反应产生一多元混合络合物，使水杨基荧光酮溶液的荧光明显猝灭，据此建立了测定痕量铁的荧光猝灭分析法。该体系的激发波长λｅｘ＝４３５．８ ｎｍ，发射波长λｅｍ＝５４０ｎｍ。铁的浓度在２～１００μｇ／Ｌ范围内有良好的线性关系；方法的检出限为０．４１μｇ／Ｌ。该方法灵敏度高，操作简便，用于天然水和人发样中微量铁的测定，结果满意。 In the HCl-NaAc buffer medium with pH3.1 ~ 5.2, the iron (Ⅲ) in the solution reacted with hydrogen peroxide (H2O2), salicylfluorone (SAF) and cetyltrimethylammonium bromide ) Reaction to produce a multi-mixed complex, so that the fluorescence of the salicylfluorone solution significantly quenched. Thus, a fluorescence quenching assay for the determination of trace iron was established. The system excitation wavelength λex = 435.8 nm, emission wavelength λem = 540nm. The concentration of iron in the range of 2 ~ 100μg / L has a good linear relationship; the detection limit of the method is 0.41μg / L. The method has high sensitivity, easy operation and is used for the determination of trace iron in natural water and human hair samples with satisfactory results.