Liquid chromatography tandem mass spectrum method for detecting sulphur amino acids in blood plasma using non-derivation method

Abstract

The invention discloses a liquid chromatography tandem mass spectrum method for detecting sulphur amino acids in blood plasma using a non-derivation method and belongs to the field of biochemical analysis and detection. The method comprises the steps that the blood plasma is added to an isotope internal standard solution, and a mixed solution is mixed evenly, then, dithiothreitol (DTT) is added to restore, and supernatant with the sulphur amino acids is obtained after protein precipitation treatment. A sample is pretreated by the adoption of the non-derivation method, the method is simple, the operation is easy, and the sample pretreatment procedures are greatly simplified; the interference for detection by matrix is reduced by the isotope internal standard, and the accuracy of homocysteine, cysteine and methionine detection is ensured. According to the liquid chromatography tandem mass spectrum method for detecting the sulphur amino acids in the blood plasma using the non-derivation method, an LC-MS / MS method is used for detecting the sulphur amino acids in the blood plasma, a multiple-reaction detection MRM scanning mode is adopted, cross interference between (i) d ( / i) (i) 3 ( / i) -methionine and homocysteine (136> 90 passage) exists, base lines of the cross interference are separated by elution conditions of a chromatography gradient, and the accuracy of the detection is ensured. The method is high in sensitivity, strong in specificity and accurate in result.

Description

technical field [0001] The invention belongs to the field of biochemical analysis and detection, and relates to a liquid chromatography tandem mass spectrometry method for detecting homocysteine ​​(Hcy), cysteine ​​(Cys) and methionine (Met) in blood plasma. Background technique [0002] Amino acids are a class of organic compounds containing amino and carboxyl groups. They are the basic components of tissue cells in the body and the basic units of proteins. It has been reported in the literature that the changes of amino acids in human plasma are closely related to the occurrence of many diseases. Hcy is an amino acid that exists in plasma and is an intermediate product in the metabolic process of Met and Cys, but it does not participate in protein synthesis. Under normal conditions, the concentration of Hcy in plasma is 5-15 mu mol / L. Genetic or acquired factors make the Hcy concentration continuously higher than the upper limit of the normal value, which is called hype...

AI Technical Summary

Problems solved by technology

[0004] Most of the current detection methods are derivatization methods, and they only focus on the determination of homocysteine. The derivatization method is cumbersome, time-consuming, and costly.

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