title: 1-(3-aminopropyl)-3-butylimidazolium bromide for carboxyl group derivatization: potential applications in high sensitivity peptide identification by mass spectrometry.
abstract: The cationic reagent 1-(3-aminopropyl)-3-butylimidazolium bromide (BAPI) was exploited for the derivatization of carboxyl groups on peptides. Nearly 100% derivatization efficiency was achieved with the synthetic peptide RVYVHPI (RI-7). Furthermore, the peptide derivative was stable in a 0.1% TFA/water solution or a 0.1% (v/v) TFA/acetonitrile/water solution for at least one week. The effect of BAPI derivatization on the ionization of the peptide RI-7 was further investigated, and the detection sensitivity was improved >42-fold via matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), thus outperforming the commercial piperazine derivatization approach. Moreover, the charge states of the peptide were largely increased via BAPI derivatization by electrospray ionization (ESI) MS. The results indicate the potential merits of BAPI derivatization for high sensitivity peptide analysis by MS.
authors.affiliation: Key Laboratory of Separation Science for Analytical Chemistry, National Chromatographic Research & Analysis Center, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
authors.forename: Xiaoqiang
authors.initials: X
authors.lastname: Qiao
authors.forename: Yuan
authors.initials: Y
authors.lastname: Zhou
authors.forename: Chunyan
authors.initials: C
authors.lastname: Hou
authors.forename: Xiaodan
authors.initials: X
authors.lastname: Zhang
authors.forename: Kaiguang
authors.initials: K
authors.lastname: Yang
authors.forename: Lihua
authors.initials: L
authors.lastname: Zhang
authors.forename: Yukui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000595:Amino Acid Sequence; D007093:Imidazoles / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods*; D010455:Peptides / Q000032:analysis* / Q000737:chemistry*; D015203:Reproducibility of Results; D020539:Sequence Analysis, Protein / Q000379:methods; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: C583483:1-(3-aminopropyl)-3-butylimidazolium; D007093:Imidazoles; D010455:Peptides