铁(Ⅲ)-1-(5-溴-2-吡啶偶氮)-2-萘酚-6-磺酸体系分光光度法测定抗坏血酸的研究

Ascorbic acid determined with Fe(Ⅲ)-5-Br-PAN-S system by spectrophotometic method

基于抗坏血酸还原Fe(Ⅲ ) 1 ( 5 溴 2 吡啶偶氮 ) 2 萘酚 6 磺酸 (简写为Fe(Ⅲ ) 5 Br PAN S)为Fe(Ⅱ ) 5 Br PAN S ,建立了分光光度法测定抗坏血酸的方法 .在 pH 5 .0的NaH2 PO4 Na2 HPO4 缓冲溶液中 ,Fe(Ⅱ ) 5 Br PAN S络合物的最大吸收峰位于波长 5 5 0nm和 75 0nm处 .在 75 0nm处 ;抗坏血酸含量在0～ 2 .4 μg/mL时符合比耳定律 .研究表明该方法操作简便、选择性较高 ,可用于药品。

As ascorbic acid can reduce Fe(Ⅲ)-5-Br-PAN-S to Fe(Ⅱ)-5-Br-PAN-S,spectrophotometic method was adopted to determine ascorbic acid in this paper.Fe(Ⅱ)-5-Br-PAN-S complex has main high peaks at λ 550 nm and 750 nm in NaH -2PO -4-Na -2HPO -4 buffer solution at pH=5.0(750 nm),the content of ascorbic acid (in ρ(VC)=0～2.4 μg/mL) is just in accordance with Beer′s law.This method is very easy to manipulate and highly selective,especially for the determination of ascorbic acid of the pharmaceuticals and the fruits.