在pH=5.0时,采用链霉素、1,10-邻菲啰啉作为显色剂,与Fe(Ⅱ)形成三元络合物测定Fe(Ⅱ)。此方法灵敏度较高(ε=4.35×10~4L·mol~(-1)cm~(-1))。线性范围较宽(0.14μg/ml～28μg/ml)。常见离子无干扰。显色相当稳定。对铁强化醋,铁强化固体饮料中Fe(Ⅱ)进行了测定,回收率分别为93～105％和92～112％。相对标准偏差分别小于5.98％和3.88％。 At pH = 5.0, Fe (Ⅱ) was determined by the formation of ternary complex with Fe (Ⅱ) using streptomycin and 1,10 - phenanthroline as chromogenic reagent. The sensitivity of this method is high (ε = 4.35 × 10 ~ 4L · mol -1 cm -1). The linear range is wide (0.14μg / ml ~ 28μg / ml). Common ions without interference. Color is quite stable. Fe (Ⅱ) in iron-fortified vinegar and iron-fortified solid beverage was determined. The recoveries were 93 ~ 105% and 92 ~ 112% respectively. The relative standard deviations were less than 5.98% and 3.88% respectively.