Antibacterial polymer coatings

Thone, J., Hollander, A., Jaeger, W., Trick, I., Oehr, C., 2003. Ultrathin antibacterial polyammonium coatings on polymer surfaces. Surf. Coat. Technol. 174-175, 584-587. 

In other cases fullerene antibacterial action takes place after photoirradiation of fulleropyrrolidinium salts. It is not yet clear if the photodynamic action implies the participation of superoxide and hydroxyl radicals (type I mechanism) or singlet oxygen (type II mechanism) but the efficacy is really interesting with the death of more than 99.9% of bacterial and fungal cells and a special selectivity for microbes over mammalian cells (Tegos et al., 2005). Also a sulfobutyl fullerene derivative is able to inhibit environmental bacteria after photoirradiation and it exerts its action on E. coli even if incorporated in coated polymer (Yu et al., 2005). 

The immobilisation of antibacterial coatings onto conductive materials such as stainless steel or carbon fibre used in orthopaedic implants was investigated by two methods. The formation of thin films by electrodeposition of polypyrrole doped with polyanions able to complex silver ions, and their characterisation by SEM, FTIR and microbiological testing is described. The alternative method, involving chemical grafting of a thin film of a quatemaiy ammonium polymer using a surface initiator, is also discussed. 2 refs. 

The synthesis and preparation of macromolecules with bactericidal or bacteriostatic properties are reviewed. The synthesis of polymers with antibacterial groups and the irmnobilisation of antibacterial reagents, such as iodine, qrratemary ammonitrm salts or antibiotics, are presented. Particular attention is paid to bacterium-adsorbing polymers, which can remove bacterial cells from aqueous media. Filter membranes coated with bacteria-adsorbing macromolectrles are also discussed. 103 refs. 

Azelaic acid (AA), 1,9-nonanedioic acid or heptane-1,7-dicarboxylic acid, is used in manifold application areas. AA is offered in the pharmaceutical field for the treatment of acne and rosacea due to its antibacterial effect [1,2]. However, AA is much more widely applied as a monomer for the production of polymers such as alkyd resins, polyamides, and impact-proof polyesters or for the synthesis of plasticizers, lubricants, lithium complex greases, corrosion inhibitors, dielectric fluids, heat-transfer fluids, metal to glass fluxes, emulsion breakers, waxes, tobacco sheet plasticizers, hot-melt coatings and adhesives, water-soluble coating resins, hydraulic fluids, fungicides, insecticides, and so on [3-7]. 

Methyl methacrylate (MMA) and sodium styrene sulfonate (SSNa) are water-soluble. These polymers behave like a low MW surfactant as they form micelles in aqueous solution in which the hydrophobic part is directed towards the centre and the hydrophilic part is situated on the periphery of the micelle. Owing to such features, amphiphilic block copolymers have wide-ranging applications in drugs, pharmaceuticals, coatings, cosmetics and paints. They also exhibit very high antibacterial activities. Oikonomou and co-workers used ATRP to prepare amphiphilic block copolymers, consisting of polymethyl methacrylate (PMMA) and poly (sodium styrene sulfonate) (PSSNa) blocks [18]. The synthesis methods are described below. 

MIC values confirmed the noticeable antibacterial activity of the fabricated polymer by the response of Enterococcus faecalis. Streptococcus pneumoniae and Staphylococcus aureus. The antimicrobial properties of pure nanofibrillated cellulose (NFC) coated with Ppy-silver composite (Scheme 7.4) films were tested on yeast Candida albicans), a Gram-negative bacterium Salmonella serovar Infantis) and a Gram-positive bacteria Listeria monocytogenes and Staphylococcus aureus) (Table 7.3) [60]. 

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