title: Peptide/protein separation with cationic polymer brush nanosponges for MALDI-MS analysis.
abstract: A cationic polymer nanobrush was synthesized, attached to a MALDI target, and used for the fractionation of peptides and proteins based on their pI, prior to analysis by MALDI-MS. The cationic polymer nanobrush was synthesized on a gold substrate by AIBN photoinitiated polymerization, using a 70:30 ratio of 2-aminoethyl methacrylate hydrochloride (AEMA):N-isopropylacrylamide (NIPAAM). This brush showed selectivity for adsorption of acidic peptides and proteins and allowed fractionation of simple two-component mixtures to be completed in less than 10 min. The brush-adsorbed biomolecules were recovered by treating the nanobrush with ammonium hydroxide, which effectively collapsed the brush, thereby releasing the trapped compounds for MALDI MS analysis. These results demonstrate that nanobrush can serve as a convenient platform for rapid fractionation of biomolecules prior to analysis by MALDI-MS.
authors.affiliation: Department of Chemistry & Biochemistry, Southern Illinois University, Carbondale, Illinois 62901-4409, United States.
authors.forename: Bojan
authors.initials: B
authors.lastname: Mitrovic
authors.forename: Stephanie
authors.initials: S
authors.lastname: Eastwood
authors.forename: VenNey
authors.initials: V
authors.lastname: Wong
authors.forename: Daniel
authors.initials: D
authors.lastname: Dyer
authors.forename: Gary
authors.initials: G
authors.lastname: Kinsel
authors.forename: Colleen
authors.initials: C
authors.lastname: Scott
mesh_terms: D000143:Acids / Q000737:chemistry; D000178:Acrylamides / Q000737:chemistry*; D000327:Adsorption; D064753:Ammonium Hydroxide; D001920:Bradykinin / Q000032:analysis; D005591:Chemical Fractionation / Q000379:methods*; D005021:Ethylamines / Q000737:chemistry*; D006878:Hydroxides / Q000737:chemistry; D007328:Insulin / Q000032:analysis; D008689:Methacrylates / Q000737:chemistry*; D009113:Muramidase / Q000032:analysis; D049329:Nanostructures / Q000737:chemistry*; D058105:Polymerization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000143:Acids; D000178:Acrylamides; D005021:Ethylamines; D006878:Hydroxides; D007328:Insulin; D008689:Methacrylates; C514459:aminoethyl methacrylate; D064753:Ammonium Hydroxide; C067295:N-isopropylacrylamide; D009113:Muramidase; D001920:Bradykinin