Amino-functionalized polymer film

Hexamethylolmelamine can further condense in the presence of an acid catalyst ether linkages can also form (see Urea Eormaldehyde ). A wide variety of resins can be obtained by careful selection of pH, reaction temperature, reactant ratio, amino monomer, and extent of condensation. Eiquid coating resins are prepared by reacting methanol or butanol with the initial methylolated products. These can be used to produce hard, solvent-resistant coatings by heating with a variety of hydroxy, carboxyl, and amide functional polymers to produce a cross-linked film. 

Functionalized conducting monomers can be deposited on electrode surfaces aiming for covalent attachment or entrapment of sensor components. Electrically conductive polymers (qv), eg, polypyrrole, polyaniline [25233-30-17, and polythiophene/23 2JJ-J4-j5y, can be formed at the anode by electrochemical polymerization. For integration of bioselective compounds or redox polymers into conductive polymers, functionalization of conductive polymer films, whether before or after polymerization, is essential. In Figure 7, a schematic representation of an amperomethc biosensor where the enzyme is covalendy bound to a functionalized conductive polymer, eg, P-amino (polypyrrole) or poly[A/-(4-aminophenyl)-2,2 -dithienyl]pyrrole, is shown. Entrapment of ferrocene-modified GOD within polypyrrole is shown in Figure 7. 

On the whole, curing procedures appear a promising way to obtain very stable polymer films. Thus, the structure of already mentioned polylysine has been revised as a block polymer involving either the a or e amino groups of lysine Vitamin Bj2 modified carbon electrodes were prepared by thermal curing of a mixture of a diamino functionalized derivative 5 and an epoxy prepolymer 6 of the araldite... 

PAMAM]. The final step of this functionalization relied on activation and cross-linking of attached dendrimers with a homobifunctional spacer (DSG or PDITC). Alternatively, after attachment of dendrimers to the surface, glutaric anhydride activated with V-h ydrox vsucc i n i m i de can be used. This surface modification yields a thin, chemically reactive polymer film, which is covalently attached to the glass support and can be directly used for the covalent attachment of amino-modified components, such as DNA or peptides (Fig. 14.2b). 

Chitobiose, a disaccharide of glucosamine, possesses two amino functions, at C-2 and C-2. These amino groups reacted with aliphatic and aromatic diacicl chlorides to give linear polyamides (11),39 These polymers afforded transparent films, which showed high permeability, indicating probable utility as permeation-dialysis membranes (Scheme 5),... 

A modified electrode using a functionalized triazole polymer film may serve as electrochemical sensor for L-methionine [89]. There, a glassy carbon electrode is modified with an electropolymerized film of 3-amino-5-mercapto-l,2,4-triazole. The sensor works at physiological pH. L-Methionine is an essential amino acid which occurs in human blood plasma, serum, and urine. An abnormal concentration of L-Methionine may cause coronary artery disease. 

Plasma-deposited allylanune films were studied by in situ ToF-SIMS before exposure to ambient air by Oran et al. [151]. The results indicated that aUylamine monomer s primary amino groups were partially transformed into other nitrogen functionalities during plasma polymerization. The same principle was applied for acrylic acid (AA) monomers. The resulting polymer films were used for surface modification of T1O2 nanoparticles [152], By means of SIMS, it was shown that AA films contain low MW oligomeric components. 

Alternating different layers of amino-functionalized silica nanoparticles (295 nm diameter) and epoxy-functionalized smaller silica nanoparticles (20 nm diameter), hybrid organic/inorganic surfaces have been constructed using the concept of covalent layer-by-layer assembly (covalent LbL) for the elaboration of films from polymers or den-drimers. ... 

Polyethylene glycol (PEG) is another well-known molecule used to reduce protein adsorption and/or platelet adhesion. Surface enrichment of a triblock oligomeric PEG containing additive from a polyurethane matrix was reported [54,55]. The authors used PEG as the active groups to suppress protein and platelet adhesion. The authors first synthesized a methylene diphenyl diisocyanate (MDI)-poly (tetramethylene oxide) (PTMO) 1000 prepolymer with a MW of approximately 4750 (PU4750), and then this prepolymer was terminally functionalized with mono amino-polyethylene oxide (PEG) with different MW (PEO550, 2000, or 5000, Table 2.3). This triblock copolymer was mixed with a polyurethane (MDI/ PTMO 1000/ethylene diamine (ED)) at different ratios in dimethylformamide (DMF) and cast into polymer films. The surface compositions of these films were evaluated by XPS. 

For covalently bonded immobilizates functionalized polymer structures have to be designed for the preparation of functionalized polymeric films on electrodes ( functionalized polymer-covered electrodes )- Some 3-functionalized thiophene derivatives have been prepared, bearing e.g. carboxy, activated ester, hydroxy, amino groups, ready for reaction with bioorganic compounds via amino, carboxy or hydroxy groups of the biomolecules as well known in peptide chemistry. 

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