High-pressure liquid chromatography of diode array detector for detecting tripolycyanamide in food

Abstract

The invention relates to a high-pressure liquid chromatography of a diode array detector for detecting tripolycyanamide in foods, which is characterized by comprising the following steps of: sampling and then extracting tripolycyanamide by 0.2-0.3% trichloroacetic acid; precipitating protein in extracting liquid by a precipitating agent; centrifugally separating supernatant in the extracting liquid, purifying and filtering; setting the method of a liquid chromatography instrument of the diode array detector to recognize the tripolycyanamide and a hydrolysis product; preparing a standard curve to obtain a regression equation of an analyzing method; detecting the tripolycyanamide by a liquid chromatograph and calculating the tripolycyanamide content. The 0.2-0.3% trichloroacetic acid extracting liquid has good extracting effect and less detecting interference; the protein is precipitated by zinc acetate and potassium ferrocyanide, the precipitation efficiency is high, and the pollution is less; the tripolycyanamide and the hydrolysis product can be detected, the result is more accurate, the used instrument and reagent are cheap and are easy for popularization, and the liquid chromatography is suitable for the detection of a plurality of samples.

Description

technical field [0001] The invention relates to a diode array detector high-pressure liquid chromatography for measuring melamine in food. Background technique [0002] Melamine, also known as triaminetriazine, referred to as triamine, is an important nitrogen-heterocyclic organic chemical raw material, white and odorless crystalline powder. The chemical is often used to make plastics, glues and flame retardants, and in some Asian countries it is also used to make fertilizer. Melamine is a banned chemical in pet food and animal feed that can cause kidney failure and death in animals after consumption. In March 2007, after the US FDA ordered the recall of nearly 100 brands of pet food because some pets got sick or even died, people began to pay close attention to the problem of melamine entering the food supply chain. In August 2008, thousands of infants and young children in China developed kidney stones due to long-term consumption of Sanlu milk powder. After testing, it ...

AI Technical Summary

Problems solved by technology

When the liquid chromatography ultraviolet detector detects food, especially dairy products, the detector is not easy to judge the hydrolysis product of melamine, so when calculating the result, the real content of melamine will be lost, or even not detected

[0005] The newly promulgated Ministry of Agriculture standard NY / T1372-2007 establishes the high-performance liquid chromatography and gas chromatography-mass spectrometry method for the determination of melamine in feed, as well as the sample pretreatment and detection method of Beijing Aijieer Technology Co., Ltd. , except the shortcoming that liquid chromatography ultraviolet detector exists, also there is following deficiency: sample pretreatment method is aimed at feed sample; After the aqueous solution is extracted, centrifugation at 8000r / min can not obtain a clarified centrifugate, which will affect the determination of the subsequent steps

Mass spectrometry methods have the disadvantages of expensive instruments, special training for operators, and long instrument detection time

For example, a liquid phase tandem mass spectrometer (HPLC-MS / MS) needs 2.6 million to 2.8 million RMB, a liquid chromatography mass spectrometer (HPLC-MS) needs 1.5 million to 2 million RMB, and a gas chromatography mass spectrometer The combined instrument (GC-MS) needs about 1 million RMB. These millions of expensive instruments are not easy to spread to the quality inspection departments of county-level cities and small and medium-sized food manufacturing enterprises. The maintenance of the instrument and the reagents and equipment consumed by starting up are expensive

The gas chromatography-mass spectrometry detection method also has the disadvantages of lengthy extraction process and derivatization, the derivatization reagents are not easy to buy, and the derivation results of this method are unstable