头发中微量铜和锌的5-Br-PADAP分光光度法测定

Determination of Trace Copper and Zinc in Hair by Spectrophotometry with 5-Br-PADAP and Multiple Masking Agent

研究了测定铜和锌时多种掩蔽剂联合掩蔽头发中的干扰离子。测定铜时用六偏磷酸钠和焦磷酸钾联合掩蔽 ;测锌时用柠檬酸钠、六偏磷酸钠和铜试剂联合掩蔽。在表面活性剂OP存在下,5_Br_PADAP显色,不经分离 ,直接在水相同时测定斑秃患者头发中的铜和锌。铜络合物的最高吸收峰在558nm,锌络合物的最高吸收峰在560nm,在25mL溶液中,铜在0～37.5mg/L,锌在0～238mg/L范围内符合beer定律。斑秃患者头发中锌和铜低于正常人。

A method for masking the interfering ions with multiple masking agent in the determination of copper and zinc in hair was established. Combined masking agents of sodium hexametaphosphate and potassium pyrophosphate were used in the determination of copper, whereas sodium citrate, sodium hexa_metaphosphate and copper reagent were used in the determination of zinc. In the presence of surfactant OP copper and zinc can be directly determined in water phase without separation using 5 _ Br _ PADAP as a chromogenic reagent. Maximum absorption wavelength is at 558 nm for copper complex and at 560 nm forzinc complex. Beer’s law is obeyed in the ranges of 0～37.5 mg/L for copper and 0～238 mg/L for zinc. The method was applied to determine trace copper and zinc in hair from patients with pelada.