摘要
本文研究了1-(5-溴-2-吡啶偶氮)-2-萘酚-6-磺酸(5-Br-PAN-S)与铁(Ⅱ)的显色反应,试验表明,在pH3～10范围内铁(Ⅱ)与5-Br-PAN-S形成稳定的络合物,络合物在550nm和750nm有二个吸收峰,其表现摩尔吸光系数分别为2.31×10~4和1.77×10~4L·mol^(-1)·cm^(-1)。络合物组成比为铁(Ⅱ):5-Br-PAN-S=1:2,络合物稳定常数为1.82×10^(24),铁量在0～60μg/25ml(750nm)范围内服从比尔定律。用本法直接测定了人发和食品中微量铁,结果满意。
Color reaction of iron(Ⅰ) with l-(5-bromo-2-pyridylazo)-2-naphthol-6-sulphonic acid (5-Br-PAN-S) has been studied. Iron(Ⅰ) reacts with 5-Br-PAN-S at pH 3-10 to form a stable 1 : 2 chelate in aqueous solution. The apparent molar absorptivity of this chelate is 2. 31 ×104(550 nm) and 1. 77×104(750 nm) L ?mol-1 ?cm-1. Beer's law is obeyed in the range of 0-60 μg/25 ml for iron (750 nm). The proposed method has been applied to the determination of trace iron in human hair and food with satisfactory results.
出处
《分析化学》
SCIE
EI
CAS
CSCD
北大核心
1994年第9期928-930,共3页
Chinese Journal of Analytical Chemistry
关键词
溴
PAN-S
铁
显色反应
Iron(Ⅰ), l-(5-Bromo-2-pyridylazo)-2-naphthol-6-sulphonic acid, Spectropho- tometry.
