title: Construction of Compact Polyelectrolyte Multilayers Inspired by Marine Mussel: Effects of Salt Concentration and pH As Observed by QCM-D and AFM.
abstract: Biomimetic multilayers based on layer-by-layer (LbL) assembly were prepared as functional films with compact structure by incorporating the mussel-inspired catechol cross-linking. Dopamine-modified poly(acrylic acid) (PAADopa) was synthesized as a polyanion to offer electrostatic interaction with the prelayer polyethylenimine (PEI) and consecutively cross-linked by zinc to generate compact multilayers with tunable physicochemical properties. In situ layer-by-layer growth and cross-linking were monitored by a quartz crystal microbalance with dissipation (QCM-D) to reveal the kinetics of the process and the influence of Dopa chemistry. Addition of Dopa enhanced the mass adsorption and led to the formation of a more compact structure. An increase of ionic strength induced an increase in mass adsorption in the Dopa-cross-linked multilayers. This is a universal approach for coating of various surfaces such as Au, SiO2, Ti, and Al2O3. Roughness observed by AFM in both wet and dry conditions was compared to confirm the compact morphology of Dopa-cross-linked multilayers. Because of the pH sensitivity of Dopa moiety, metal-chelated Dopa groups can be turned into softer structure at higher pH as revealed by reduction of Young's modulus determined by MFP-3D AFM. A deeper insight into the growth and mechanical properties of Dopa-cross-linked polyelectrolyte multilayers was addressed in the present study. This allows a better control of these systems for bioapplications.
authors.affiliation: State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China.|Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany.
authors.forename: Weina
authors.initials: W
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China.
authors.forename: Yisheng
authors.initials: Y
authors.lastname: Xu
authors.affiliation: Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Backes
authors.affiliation: State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China.
authors.forename: Ang
authors.initials: A
authors.lastname: Li
authors.affiliation: Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany.
authors.forename: Samantha
authors.initials: S
authors.lastname: Micciulla
authors.affiliation: Chemistry Department, Bogazici University , Bebek, Istanbul 34342, Turkey.
authors.forename: A Basak
authors.initials: AB
authors.lastname: Kayitmazer
authors.affiliation: State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China.
authors.forename: Li
authors.initials: L
authors.lastname: Li
authors.affiliation: State Key Laboratory of Chemical Engineering, East China University of Science and Technology , Shanghai 200237, China.|Engineering Research Center of Materials Chemical Engineering of Xinjiang Bintuan, Shihezi University , Xinjiang 832000, China.
authors.forename: Xuhong
authors.initials: X
authors.lastname: Guo
authors.affiliation: Stranski-Laboratorium für Physikalische und Theoretische Chemie, Technische Universität Berlin , Strasse des 17. Juni 124, D-10623 Berlin, Germany.
authors.forename: Regine
authors.initials: R
authors.lastname: von Klitzing
mesh_terms: D000180:Acrylic Resins / Q000138:chemical synthesis / Q000737:chemistry*; D000818:Animals; D040761:Biomimetic Materials; D049872:Bivalvia; D002614:Chelating Agents / Q000138:chemical synthesis / Q000737:chemistry*; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D055119:Elastic Modulus; D006863:Hydrogen-Ion Concentration; D000071228:Polyelectrolytes / Q000138:chemical synthesis / Q000737:chemistry*; D011094:Polyethyleneimine / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000180:Acrylic Resins; D002614:Chelating Agents; D000071228:Polyelectrolytes; C006903:carbopol 940; D004295:Dihydroxyphenylalanine; D011094:Polyethyleneimine