超高灵敏显色反应及其应用的研究——食品中痕量锰的光度法测定

Study of Ultra High Sensitive Colour Reactions and Its Application-Spectrophotometric Determination of Trace Manganese in Foods

本文研究了在表面活性剂CTMAB和辅助剂H_2O_2、phen存在下,T(4-MP)PS_4与Mn(Ⅱ)超高灵敏显色反应的光度法测定条件。在溶液pH 9.15—9.35,拂水溶中加热6_min,配合物稳定形成。试剂最大吸收峰和形成配合物后的试剂消失峰于420nm。表观摩尔吸光系数为2.23×10~7L·mol^(-1)cm^(-1)。Mn(Ⅱ)浓度在0—50ng/25ml范围内符合比耳定律。本法用于淀粉、茶汤中痕量锰的测定,结果满意。

Spectrophotometric determination of ultratrace Manganese (Ⅱ) with o-phenanthroline-hydrogen peroxide-porphyrine-CTMAB system have been studied. The complex is formed by heating at 100℃ for 6min and at pH 9.25. The detreminate wavelength of the complex lies at 420nm. The apparent molarabsorptivity of the complex is 2.23×107L·mol-1·cm-1.Beer' Law is obeyed for Mn(Ⅱ) in the range of0-50ng/25ml. This method can be used for the determination of trace manganese(Ⅱ) in tea soup andstarch. The results agreed favorobly with those obtained by AAS.