摘要
阿拉伯树胶存在下,在pH 5.0NaAc-HAc缓冲溶液中,铁(Ⅱ)与邻菲啰啉(phen)和亮黄(BY)反应生成稳定的离子缔合物[Fe(phen)3]BY,在离子缔合物的最大吸收峰478nm处体系吸光度明显增强,建立了分光光度法测定微量铁的新方法。试验了酸度、试剂用量、增效剂、反应温度和反应时间的影响,确定了最佳反应条件。铁(Ⅱ)浓度在0～1.0μg/mL范围内符合比耳定律,表观摩尔吸光系数为2.95×104 L/mol/cm,检出限为20.44μg/L。方法用于测定酱油中铁含量,结果与原子吸收分光光度法一致,相对标准偏差分别为1.1%和0.8%(n=5),平均回收率分别为100.5%和98.3%。
In presence of arabic gum, Fe （ Ⅱ ） reacts with phen and bright yellow （BY） to form a stable ion-association complex I-Fe（phen）3-]BY in NaAc-HAc buffer solution at pH 5.0, which results in an enhancement of absorbence with the maximum absorption peak at 478 nm. Based on this fact, a new spectrophotometric method for the determination of trace iron was proposed. The optimal conditions of measurements of iron including acidity, reagents dosage, synergist, reaction temperature and reaction time were studied. The Beer＇s law was obeyed in the range of 0-1.0 μg/mL for Fe （ Ⅱ ）. The appar- ent molar absorption coefficient was 2.95 X 104 L/mol/cm, and the limit of detection was 20.44 μg/L. The method has been applied to determination of iron content in sauce samples. The results agreed well with those obtained by atomic absorption spectrometry. RSDs of 5 determinations were 1.1 and 0.8 %, respectively. Average recoveries were 100.5 %and 98.3 %, respectively.
出处
《中国调味品》
CAS
北大核心
2012年第10期93-97,共5页
China Condiment
关键词
分光光度法
铁
酱油
spectrophotometry iron sauce
