title: Further investigation of a peptide extraction method with mesoporous silica using high-performance liquid chromatography coupled with tandem mass spectrometry.
abstract: Mobil Composition of Matter No. 41 (MCM-41) was the most frequently used mesoporous silica material to extract peptides from complex biological samples. However, there were confusing extraction conditions and large extraction efficiency variance among related reports, which resulted from unclear understanding about the interaction between the material and peptides. In this study, the extraction mechanism was investigated with one set of tryptic peptides by using high-performance liquid chromatography coupled with triple quadrupole mass spectrometry. Generally, hydrophobic interaction and electrostatic attraction were two major driving forces for extraction of peptides, while electrostatic repulsion greatly weakened the interaction between the material and peptides with isoelectric points below the pH. With most peptides positively charged and MCM-41 slightly negatively charged, most efficient extraction was obtained at pH 3, and it was proved that electrostatic and hydrophobic interaction acted in synergy for extraction of all the peptides. A mixed solution of acetonitrile with buffers of high pH or ion strength was demonstrated to be favorable for elution, which performed much better than the commonly used eluate (mixture of acetonitrile with 0.1% trifluoroacetic acid). Finally, under optimum conditions, it was found that extraction efficiency of MCM-41 for protein digest and human serum was greatly improved.
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China.|University of Chinese Academy of Sciences, Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Du
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China.
authors.forename: Dapeng
authors.initials: D
authors.lastname: Wu
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China.
authors.forename: Yafeng
authors.initials: Y
authors.lastname: Guan
mesh_terms: D002851:Chromatography, High Pressure Liquid; D057927:Hydrophobic and Hydrophilic Interactions; D010316:Particle Size; D010455:Peptides / Q000737:chemistry / Q000302:isolation & purification*; D016062:Porosity; D012822:Silicon Dioxide / Q000737:chemistry*; D055672:Static Electricity; D013499:Surface Properties; D053719:Tandem Mass Spectrometry
chemical_list: C509968:MCM-41; D010455:Peptides; D012822:Silicon Dioxide
keywords: Extraction mechanism; Mesoporous silica; Peptide extraction; Serum