Study On Amino Acids Separation By Micellar Liquid Chromatographic Method

Micellar solution as mobile phase promoted the formation of a new liquid chromatography-micellar liquid chromatography.Micellar liquid chromatography is an "green" and cheap alternative method to traditional reversed-phase liquid chromatography over the past three decades.Developing a detection method with high sensitivity and selectivity is a difficult task,and micellar liquid chromatography is one of the most promising separation methods.Amino acids,which are the constituent units of proteins,play an important role in energy intake and metabolism.At the same time,many diseases in the human body are related to the level of amino acids.The detection of amino acids in biological samples have great significance in the prevention and diagnosis of diseases.This research was based on micellar liquid chromatography and novel surfactants,and two new types of stationary phases are applied to the detection of biological samples.The research work is as follows:1)A high submicellar liquid chromatography method with isocratic elution was established,and the amino acids in the Compound Amino Acid Injection was determined.For the first time,a novel zwitterionic surfactant,dodecyl dimethyl betaine was used to elute 17 amino acids in 35 minutes.The derivative test was used to evaluate the chromatographic peaks and the different conditions on the peak shape were compared during the optimization process.The concentration of the surfactant,the pH value of the mobile phase were evaluated by this method.After that,the possible separation mechanism was discussed.This method reduces the time of secondary equilibrium and the operation procedure is simple which compared with the gradient elution method using micellar liquid chromatography.2)A micellar liquid chromatography method for the isocratic separation of aromatic amino acids and branched-chain amino acids by 2-methylimidazole-column was established.The surfactant concentration,pH value of the mobile phase and the content of organic solvent were researched.In addition,the retention mechanism based on the 2-methylimidazole column was preliminarily investigated,confirming that the 2-methylimidazole column has the retention ability to poor polar and non-polar compounds.3)A micellar liquid chromatography method for separating aromatic amino acids and branched-chain amino acids which based on 1,6-hexanediol dimethacrylate monolithic column was established.The optimum chromatographic conditions were obtained through optimization of different conditions,and biological samples containing aromatic amino acids and branched-chain amino acids were determined.The results showed that the biological samples detected by this method was diluted 1 times.This provides new methods for the detection of biological samples.At the same time,the research showed that monolithic columns have potential for biological samples detection.