【摘要】 研究铁(Ⅱ)与邻菲啰啉和刚果红的络合反应,建立分光光度法测定铁含量的新方法。通过试验优化酸度、邻菲啰啉用量、刚果红用量、反应温度和反应时间等测定条件。结果表明:最大吸收波长为540nm,表观摩尔吸光系数为4.4×104 L/mol·cm,铁(Ⅱ)浓度在0~0.8μg/mL范围内符合比尔定律,检出限为8.8μg/L。该方法用于测定酵母抽取物中的铁含量,结果与国标法一致,相对标准偏差为0.48%~0.77%(n=5),回收率为98.2%~101.6%。更多还原

【Abstract】 A new method of spectrophotometry is established for determination of iron content based on the complex reaction of Fe(Ⅱ)and phen-congo red.The determination conditions of Fe(Ⅱ)including acidity,phen dosage,congo red dosage,reaction temperature and reaction time are optimized by experiments.The results show that the maximum absorption wavelength is at 540nm,the apparent molar absorption coefficient is 4.4×104 L/mol·cm,the concentration of Fe(Ⅱ)within 0~ 0.8μg/mL obeys Beer’s Law,and the detection limit is 8.8μg/L.The method is applied for the determination of iron content in yeast extract.The results obtained by this method are in accordance with those obtained by the national standard method.The RSD is 0.48% ~0.77%(n=5).The recovery is 98.2%~101.6%.更多还原