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早在1956年就报道了N-二甲基亚硝胺具有致癌作用。从此以后,科学家们对N-亚硝基化合物进行了广泛深入的研究,发现这类化合物有300多种,其中约90％具有致癌活性,这类化合物,在鱼、肉、蛋、奶以及腌渍菜等食品中含可检测出痕迹量,因而促使人们进行更灵敏的检测方法的研究。由于Z-亚硝胺的挥发性、光解性以及氧化还原性,使得建立检测方法的难度很大。迄今为止,还没有一个通用的规范化的方法为大家所接受。一般认为气相色谱—质谱(GC—MS)法,气相色谱—热能分析(GC—TEA)法是最佳方法,但由于这两个方法设备昂贵,难于推广,而气相色谱—电子捕获(GC—ECD)法是检测N-亚硝胺的最灵敏的分析方法之一,其检测限可达PPt级。GC—ECD法的检测原理是:用H_2O_2+CF_3COOH将N-亚硝胺氧化成相应的N-硝胺。
As early as 1956, it was reported that N-dimethylnitrosamine has a carcinogenic effect. Since then, scientists have conducted extensive and in-depth research on N-nitroso compounds and found that there are over 300 kinds of these compounds, of which about 90% are carcinogenic. Such compounds are found in fish, meat, eggs, milk and pickled Vegetables and other foods containing detectable amount of traces, prompting people to conduct more sensitive detection methods. Because of the volatility, photodegradability and redox activity of Z-nitrosamines, it is very difficult to establish a detection method. So far, no universal standardization method has been accepted by all. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-thermal analysis (GC-TEA) are generally considered as the best methods. However, these two methods are expensive and difficult to be generalized. GC- ECD) method is one of the most sensitive analytical methods for the detection of N-nitrosamines with a detection limit of up to PPt. The principle of GC-ECD detection is that N-nitrosamines are oxidized to the corresponding N-nitroamines by H 2 O 2 + CF 3 COOH.