基于重氮化-偶合显色反应的纺织品中禁用偶氮染料快速定性筛选方法

A Rapid Qualitative Screening Method Based on Diazotization-Coupling Color Reaction for Determination of Banned Azo Dyes in Textile

利用芳香胺的重氮化-偶合显色反应原理,建立了纺织品中24种禁用芳香胺的快速定性筛选测定方法。样品经还原后,先用10 mL叔丁基甲醚萃取,再用5 mL HCl反萃取,达到净化和脱色的目的,HCl萃取液中加入0.05 mL NaNO2,重氮化反应10 min,滴加0.5 mL氨基磺酸铵除去多余的NaNO2,加入1mL邻甲氧基苯酚与重氮盐偶联显色。根据萃取液是否显色,快速地对样品中是否含有禁用偶氮染料作出初步判断。方法的检出限低于15 mg/kg,上千个实际样品测试无假阴性,假阳性概率为28%。本方法无需大型色谱仪器设备,与仪器测定方法相比,前处理时间缩短了约60%,节约了约90%的试剂费用。

Based on the principle of diazotization-coupling color reaction of aromatic amines, a rapid qualita- tive screening method for detecting 24 banned aromatic amines dyes in textile was developed. After reduction reaction, sample solutions were extracted with 10 mL t-butyl methyl ether and 5 mL hydrochloric acid respec- tively. Then 0.05 mL sodium nitrite was mixed into extract liquids and maintained for 10 min. To get rid of redundant sodium nitrite, O. 5 mL Ammonium sulfamate was added in. Thereafter 1 mL of guaiacol was added as color reagent. According to the condition of presence or absence of color-reaction, preliminary judgment of whether the textiles containing banned azo dyes could be done. The results showed that the detection limit of the method was less than 15 mg/kg. It met the requirements of the current regulation limits. The test results of more than 1000 actual sample showed that there was no false negative case of this method and false positive rate was 28%. Comparing with current testing means, this method could shorten the pre-processing time more than 60%, and saved reagent costs more than 90%. The whole test procedure could be processed without any chromatographic equipment.