高碘酸钾-酸性品红-NTA-DDMAA体系催化光度法测定良量锰

Catalytic Spectrophotometric Determination of Trace Amount of Manganese by Potassium Periodate-Fuchsin Acid-Nitrilo Triaceticacid-Dodecyl Dimethylamino Acid System

摘要: 报道了以氨三乙酸为活化剂,以N-十二烷基二甲基铵基乙酸(DDMAA)为增敏剂,高碘酸钾氧化酸性品红催化光度法测定痕量锰的新方法,在DDMAA存在下,灵敏度提高了7倍(Mn²⁺量为1.2～2.4μg/L)和14倍(Mn²⁺量为2.4～5.2μg/L),相对标准偏差为2.0%,检出限为1.4×10^-7g/L,可用于茶叶中锰的测定.

Abstract: A new catalytic spectrophotometric method for the determination of trace amount of Mn(∏) has been developed. The method is based on the oxidation of fuchsin acid with potassium periodate in the presence of nitrilo triaceticacid as an activator and dodecyl dimethylamino acetic acid (DDMAA) as a sensitizer. The sensitivity is increased by 7 times(the rage 1.2～ 2.4 μg/L) and 14 times(the rage 2.4～5.2 μg/L) than that in the absence of the DDMAA. The relative standard deviation was 2.0% for 4.0 μg/L Mn(∏)(11 replicates). The limit of detection for Mn is 1.4～10^-10 mg/L. The method has been succesfully applied to the determination of Mn in tea sample.