title: (E)-Propyl α-Cyano-4-Hydroxyl Cinnamylate: A High Sensitive and Salt Tolerant Matrix for Intact Protein Profiling by MALDI Mass Spectrometry.
abstract: Low-abundance samples and salt interference are always of great challenges for the practical protein profiling by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS). Herein, a series of carboxyl-esterified derivatives of α-cyano-4-hydroxycinnamic acid (CHCA) were synthesized and evaluated as matrices for MALDI-MS analysis of protein. Among them, (E)-propyl α-cyano-4-hydroxyl cinnamylate (CHCA-C3) was found to exhibit excellent assay performance for intact proteins by improving the detection sensitivity 10 folds compared with the traditional matrices [i.e., super2,5-dihydroxybenzoic acid (superDHB), sinapic acid (SA), and CHCA]. In addition, CHCA-C3 was shown to have high tolerance to salts, the ion signal of myoglobin was readily detected even in the presence of urea (8 M), NH4HCO3 (2 M), and KH2PO4 (500 mM), meanwhile sample washability was robust. These achievements were mainly attributed to improved ablation ability and increased hydrophobicity or affinity of CHCA-C3 to proteins in comparison with hydrophilic matrixes, leading to more efficient ionization of analyte. Furthermore, direct analysis of proteins from crude egg white demonstrated that CHCA-C3 was a highly efficient matrix for the analysis of low-abundance proteins in complex biological samples. These outstanding performances indicate the tremendous potential use of CHCA-C3 in protein profiling by MALDI-MS. Graphical Abstract ᅟ.
authors.affiliation: College of Chemistry, Jilin University, Changchun, 130012, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Wang
authors.affiliation: College of Chemistry, Jilin University, Changchun, 130012, China.
authors.forename: Zhaohui
authors.initials: Z
authors.lastname: Xiao
authors.affiliation: Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China. xiaocs@ciac.ac.cn.
authors.forename: Chunsheng
authors.initials: C
authors.lastname: Xiao
authors.affiliation: College of Chemistry, Jilin University, Changchun, 130012, China.
authors.forename: Huixin
authors.initials: H
authors.lastname: Wang
authors.affiliation: College of Chemistry, Jilin University, Changchun, 130012, China.
authors.forename: Bing
authors.initials: B
authors.lastname: Wang
authors.affiliation: College of Chemistry, Jilin University, Changchun, 130012, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Li
authors.affiliation: Key Laboratory of Polymer Ecomaterials, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, 130022, China.
authors.forename: Xuesi
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Chemistry, Jilin University, Changchun, 130012, China. guoxh@jlu.edu.cn.
authors.forename: Xinhua
authors.initials: X
authors.lastname: Guo
mesh_terms: D000818:Animals; D002417:Cattle; D002645:Chickens; D003373:Coumaric Acids / Q000737:chemistry*; D004527:Egg Proteins / Q000032:analysis; D004529:Egg White / Q000737:chemistry; D004951:Esterification; D006801:Humans; D011506:Proteins / Q000032:analysis*; D011817:Rabbits; D012492:Salts / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013552:Swine
chemical_list: D003373:Coumaric Acids; D004527:Egg Proteins; D011506:Proteins; D012492:Salts; C007175:alpha-cyano-4-hydroxycinnamate
keywords: Esterified α-cyano-4-hydroxycinnamic acid; MALDI-TOF MS; Proteins; Salt-tolerance; Sensitivity