The Shandong Provincial Inspection and Quarantine Bureau completed the Science and Technology Plan of the General Administration of Quality Supervision, Inspection and Quarantine, "Development of Rapid Detection Kit for Hazardous Substances in Ecological Textiles", systematically studied the colorimetric determination method of banned azo dyes harmful to human health in textiles, and developed a simple method. Fast, no need for large-scale instruments and equipment, high sensitivity dyeing textiles, banned azo dye rapid screening test kit, achieved a major breakthrough in dyeing textile banned azo dye detection technology, opened up a fast, adaptable and fast Qualitative screening detection pathways.

The banned azo dye refers to a kind of azo dye which may cause carcinogenic aromatic amine after cleavage and change the structure and function of human DNA through activation, and finally cause human diseases and cancer. These dyes are one of the most important quality control projects in the current international textile and apparel trade, and one of the most basic quality indicators of eco-textiles.

Traditional technology cycle costs are high

China's mandatory national standard GB 18401 "National Textile Product Basic Safety Technical Specifications", Germany's "Food and Consumer Goods Law", the European Union's Eco-Lable and the most widely used textile ecological mark Oeko-Tex Standard 100 "ecological textiles" Standard 100 and other domestic and foreign regulations have included it in the ban, becoming one of the most important inspection items for import and export textiles.

The number of carcinogenic aromatic amines currently banned has increased to 24, and the detection of the other 23 aromatic amines can be carried out simultaneously, except that the detection method of 4-aminoazobenzene is slightly different. For the detection of banned azo dyes, the conventional method is to reduce the sample and then measure it by gas chromatography, liquid chromatography, gas chromatography/mass spectrometry, liquid chromatography/mass spectrometry. The method is mature, accurate and sensitive. However, the pre-treatment is complicated, the instrument needs to be equipped with precision, the inspection cycle is long, and the inspection cost is high. It is necessary to have professional technicians and harsh conditions. Judging from the detection of banned azo dyes in textiles in recent years, on the one hand, the detection business volume has doubled and the detection pressure has increased sharply; on the other hand, the positive detection rate has decreased year by year, and the work of accurate quantitative analysis has been greatly reduced.

In view of the above problems, the establishment of a rapid screening method that does not require relying on large-scale chromatography instruments to be simple and low-cost is an urgent need for the ban of azo dye detection in textiles.

Rapid and low-cost screening of aromatic amines

The banned azo dye detection kit technology proposes a rapid detection method for banned azo dyes in dyed textiles, which solves the dependence of traditional determination methods on large-scale chromatography instruments and meets the needs of current rapid screening.

According to the structural characteristics of aromatic amines, the kit technology introduces the mechanism of diazotization-coupling color reaction, effectively optimizes the conditions of diazotization reaction and coupling reaction, and uses tert-butyl methyl ether and hydrochloric acid liquid-liquid extraction technology to realize aromatic amines. The extraction and the reaction solution were decolorized, and o-methoxyphenol was used as a color developing agent to determine the aromatic amine by color development. A rapid screening test method for banned azo dyes in dyed textiles was established, and a major breakthrough was achieved in the banned azo dye detection technology for dyed textiles.

This technology is compared with the current domestic and international methods for banned azo dye detection: no chromatographic instrument is required, the required instrument is only a reducing water bath, the instrument cost is less than 1% of the existing instrument detection method; the pretreatment step is simplified to reduction and extraction Two steps of decolorization, easy to operate, the time to test one sample is only 34% to 40% of the existing method; no aromatic amine standard, diatomaceous earth extraction column, etc., the reagent dosage is small, the required reagent cost is only There are 3%-8% of the detection methods (take the technical center of Shandong Inspection and Quarantine Bureau as an example. In 2011, a total of 4000 batches of azo samples were tested. Using this technology, only one reagent can save costs by 220,000.) The method is simple and fast. low cost. A rapid screening test for the banned azo dyes in textiles was achieved.

Research results have broad application prospects

The technology has been tested by thousands of actual samples at the Technical Center of Shandong Inspection and Quarantine Bureau. At the same time, it is at the Technical Center of Jiangxi Entry-Exit Inspection and Quarantine Bureau, the Technical Center of Jiangsu Entry-Exit Inspection and Quarantine Bureau, the Technical Center of Zhejiang Entry-Exit Inspection and Quarantine Bureau, and Shanghai Tiantian. Six units of Xiangxiang Group, Qingdao Textile Fiber Inspection Institute and Shandong Inspection and Certification Group Shandong Testing Co., Ltd. conducted on-site method verification. The kit brought the kit and the experimenter, and took more than 20 blind samples from each of the daily samples tested for on-site testing. The kit test results were compared with the actual instrument test results. The verification results were as follows: 42 positive samples were detected, and the detection rate of the method was 100%, and there was no false negative. 1040 negative samples were detected, and 285 samples showed false positive results, and the probability of false positives was 27%.

In March 2013, at the Textile Professional Committee Working Conference and Standards Review Meeting, the technology was introduced again due to the opening of the standard. The Beijing Inspection and Quarantine Bureau, Shanghai Inspection and Quarantine Bureau, Zhejiang Inspection and Quarantine Bureau and Shenzhen Inspection and Quarantine Bureau were present. The first-line brothers who are engaged in the testing of textile azo dyes are extremely interested, and they are asking for a kit to let them go back and try. At present, the three units have actually applied and feedback the results. The general reaction method is simple, fast, and practical. It is recommended to be converted into product promotion and application as soon as possible.

The research results of this project have broad application prospects. On the one hand, for the inspection organization, the inspection cycle of textiles and garments can be shortened, the inspection cost can be reduced, and the current high-throughput, low-cost inspection needs can be met. On the other hand, the inspection of harmful substances in textiles and garments can be extended to factories, workshops, warehouses, goods factories and other places in advance. China's textile industry has the characteristics of small scale and large number of enterprises. The rapid testing will facilitate the selection of raw materials, improve product quality and improve the market competitiveness of enterprises, which will help enterprises to improve quality and reduce losses, and protect the health of our people. And the protection of foreign trade exports has an important significance.

Link>>

The research team applied for the national invention patent “Method for rapid detection of banned azo dyes in dyed textiles” and was authorized (patent number: ZL 201110350255.7). "Rapid Determination of Disabling Azo Dyes in Textiles - Kit Screening Method" (2012B406) was transformed into an industry standard for inspection and quarantine, and published in the Journal of Analytical Chemistry with the highest impact factor in domestic chemical journals: "Based on Diazotization - The rapid qualitative screening method for banned azo dyes in textiles coupled with color reaction is included in SCI. Extensive and effective promotion within and outside the industry through patents, standards, and articles. The research group was also invited to participate in the "2013 International Inspection and Testing Technology and Equipment Expo and National Inspection and Testing Academic Conference", and gave a special speech on the rapid detection technology.