Multifunctional layer-by-layer modified chitosan/poly(ethylene glycol) hydrogels

We report the surface modification of chitosan/poly(ethylene glycol) (chitosan/PEG) hydrogel materials via layer-by-layer (LbL) technique using stimuli-responsive polymers. Water-soluble complexes of Tannic Acid (TA) and a broad-spectrum antibiotic, Ciprofloxacin (Cipro) were prepared and co-assembled at the surface of Chitosan/PEG hydrogels with poly(N-vinyl caprolactam) (PVCL). Compared to the bare hydrogels, the surface spreading and proliferation of human fibroblasts were significantly enhanced on precast hydrogels coated with TA-Cipro/PVCL multilayers. LbL coating also provided enhanced Cipro release from the hydrogel surface at 37 degrees C compared to bare hydrogels. TA-Cipro/PVCL coated hydrogels showed antibacterial activity through chitosan and temperature-induced release of Cipro from multilayers. Chitosan and Cipro showed a coordinated antibacterial effect on Eschericia coli and Bacillus cereus, reducing their minimum inhibitory concentration (MIC). This effect was more pronounced on B. cereus. LbL modification of chitosan-based hydrogels using stimuli responsive polymers can be advantageous for bringing multiple functionalities to these materials without sacrificing their intrinsic properties such as antibacterial activity and biocompatibility. Such LbL-coated hydrogels hold promise in wound treatment as they may promote fibroblast proliferation and skin tissue regeneration.


Electrochemical polymerisation of 2-aminofluorene in ethylalcohol/water medium
Imamoglu, T; Önal, Ahmet Muhtar (Elsevier BV, 2004-08-01)
Electrochemical polymerisation of 2-aminofluorene, 2AF, was investigated in ethylalcohol/water mixture (3:2, v:v) in the presence of HClO4 as the supporting electrolyte via constant potential electrolysis, CPE. Prior to CPE, electrochemical behaviour of the monomer was investigated in the same solvent electrolyte couple utilising cyclic voltammetry, CV. Electrochemical polymerisation of the monomer yielded insoluble, dark bluish-green, conducting polymer deposit on the electrode surface. Characterisation of...
KISAKUREK, D; YIGIT, S (Elsevier BV, 1991-01-01)
Bis(4-bromo-2,6-dichlorophenoxo) ethylenediamine copper(II) complex has been polymerized using electro-initiation by constant potential electrolysis, in dimethylformamide-tetrabutylammonium fluoroborate solvent-supporting electrolyte couple, at room temperature under air or N2. The process leads to low molecular weight (5.6 x 10(3)) linear poly(dichlorophenylene oxide). The structures of the polymers were determined by H-1-NMR and C-13-NMR. The kinetics of the polymerization were followed by in situ cycl...
Layer-by-layer films of block copolymer micelles with cores exhibiting upper critical solution temperature behaviour
Ustoglu, Cansu; Çağlı, Eda; Erel Göktepe, İrem (Elsevier BV, 2017-11-01)
We report on preparation of block copolymer micelles with cores exhibiting upper critical solution temperature (UCST) behavior in the range of 40-45 degrees C at pH 7.5 and incorporation of such micelles into layer-by-layer (LbL) films to obtain UCST-type milltilayer films. Pyridine units of poly(2-vinylpyridine-b-ethylene oxide) (P2VP-b-PEO) were partially quaternized and its self-assembly into micellar aggregates was achieved in the presence of potassium hexacyanoferrate (K3Fe(CN)(6)p) at pH 7.5 at either...
Immobilization of invertase and glucose oxidase in poly 2-methylbutyl-2-(3-thienyl) acetate/polypyrrole matrices
Isik, S; Alkan, S; Toppare, Levent Kamil; Cianga, I; Yagci, Y (Elsevier BV, 2003-12-01)
Immobilization of invertase and glucose oxidase in conducting polypyrrole and copolymers of poly 2-methylbutyl-2-(3-thienyl) acetate with pyrrole were achieved via electrochemical method. Sodium dodecyl sulphate was found to be the most suitable supporting electrolyte. Maximum reaction rate, Michaelis-Menten constant and optimum temperatures were determined for native and immobilized enzymes. Storage and operational stabilities of enzyme electrodes were also investigated.
Multi-colored electrochromic polymer with enhanced optical contrast
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A new it-conjugated monomer was synthesized which contains an electron-donating unit 3 4-ethylenedioxythiophene and electron withdrawing quinoxaline-based heterocycle to examine the effects of imine unit on the optoelectronic and redox properties of the resulting polymer Electroactivity of monomer and electrochemical redox behavior of its polymer were investigated by cyclic voltammetry An irreversible anodic wave at +0 85 V vs Ag wire reference electrode corresponding to the monomer oxidation was observed S...
Citation Formats
B. Onat, S. Ulusan, S. Banerjee, and İ. Erel Göktepe, “Multifunctional layer-by-layer modified chitosan/poly(ethylene glycol) hydrogels,” EUROPEAN POLYMER JOURNAL, pp. 73–86, 2019, Accessed: 00, 2020. [Online]. Available: