title: [Influence of pH value of mobile phase on phosphopeptide enrichment selectivity under hydrophilic interaction liquid chromatography mode by using Click OEG-CD matrix].
abstract: The digest of the standard protein alpha-casein was used as the objective to investigate the influence of pH value of mobile phase on phosphopeptide enrichment selectivity by using Click OEG-CD matrix. Disodium phenyl phosphate was primarily selected as the model sample. The results indicated that phosphate group was difficultly to be ionized when the pH value of mobile phase was below its pKa value. The retention of disodium phenyl phosphate on the Click OEG-CD matrix was not based on ion exchange interaction, leading to the weak retention. The influence of pH value (2, 4 and 6) of mobile phase under hydrophilic interaction liquid chromatography (HILIC) mode on phosphopeptide enrichment selectivity was investigated taking the digest of alpha-casein as a sample. Phosphopeptides could not be enriched on the matrix with the pH value of 2; phosphopeptides could be enriched on the matrix and the elution window was narrow with the pH value of 4; phosphopeptides could be enriched on the matrix while the elution window was broad with the pH value of 6. According to the investigation, Click OEG-CD matrix could be better applied in phosphopeptide enrichment.
authors.affiliation: College of Pharmacy, Dalian Medical University, Dalian 116044, China.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Zhimou
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Xiuling
authors.initials: X
authors.lastname: Li
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Xinmiao
authors.initials: X
authors.lastname: Liang
mesh_terms: D002853:Chromatography, Liquid; D057930:Click Chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D010748:Phosphopeptides
chemical_list: D010748:Phosphopeptides