Biocidal Polymers Research Articles

Antibacterial porous polymeric monolith columns with amphiphilic and polycationic character on cross-linked PMMA substrates for cell lysis applications

The application of porous polymeric monolith (PPM) columns as an effective tool for bacterial cell lysis within microfluidic chips is demonstrated. By taking advantage of the large surface area and controllable pore size inherent to PPMs, we developed a double mechanism cell lysis technique. The bacterial cell wall is mechanically sheared by flowing through the porous medium of the PPM column, but it is also damaged and disintegrated by physical contact with the antibacterial polymeric biocide covering the porous surface. This leads to leakage of the intracellular contents. The stable and non-leaching antibacterial column introduced in this work alleviates the need for chemical or enzymatic lysins and their potential release of polymerase chain reaction (PCR) inhibitors. The PPM columns were obtained by the photoinitiated free radical copolymerization of n-butyl methacrylate (BuMA) and N-(tert-butyloxycarbonyl)aminoethyl methacrylate (Boc-AEMA) in the presence of a cross-linker and porogenic solvents. The porous network was synthesized directly inside a microfluidic channel fabricated in a cross-linked poly(methyl methacrylate) (X-PMMA) substrate by laser micromachining. After removing the Boc protecting group with phosphoric acid, an amphiphilic and cationic network structure reminiscent of synthetic mimics of antimicrobial peptides (SMAMPs) was obtained. The antibacterial activity of the PPM columns was tested against Bacillus subtilis (B. subtilis) and Escherichia coli (E. coli) cells. Cell lysis was evidenced by DNA release, which was then amplified by PCR and confirmed by gel electrophoresis, to verify that the antibacterial monolithic columns did not strongly interfere with the PCR process.

Straw N-halamines: Evaluation in single and multistage filtration systems

New N-halamines (I-Cl and II-Cl) based on cellulose extracted from rice straw have been evaluated in single and multistage filtration systems against bacteria and viruses. Escherichia coli and Staphylococcus aureus were used as examples of Gram-negative and Gram-positive bacteria respectively while PRD1 bacteriophage was used as an example for viruses. II-Cl has achieved 9 log reductions in viable counts against E. coli in 2h and S. aureus in 1h while it has achieved 7 log reductions against PRD1 in 5h. The particle size of prepared materials was modified as well as the flow rate through the filtration systems. The antimicrobial activity of modified cellulose was proved to be comparable to some synthetic biocidal polymers from the same type in similar water treatment systems.

Biocidal polymers: synthesis and antimicrobial properties of benzaldehyde derivatives immobilized onto amine-terminated polyacrylonitrile.

BackgroundThe design and applications of antimicrobial polymers is a growing field. Antimicrobial polymers can help to solve the problems associated with the use of conventional antimicrobial agents. Polymers with active functional groups can act as a carrier system for antimicrobial agents. In our study, we aim to prepare and develop some antimicrobial polymers for biomedical applications and water treatment.ResultsThe antimicrobial polymers based on polyacrylonitrile (PAN) were prepared. Functional groups were created onto polyacrylonitrile via amination using different types of diamines such as ethylenediamine (EDA) and hexamethylenediamine (HMDA) to yield amine-terminated polymers. Antimicrobial polymers were obtained by immobilization of benzaldehyde and its derivatives which include, 4-hydroxybenzaldehyde and 2,4-dihydroxybenzaldehyde onto amine-terminated polymers. The antimicrobial activity of the prepared polymers against different types of microorganisms including Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Pseudomonas aeruginosa; Escherichia coli; and Salmonella typhi) as well as fungi (Aspergillus flavus, Aspergillus niger, Candida albicans, Cryptpcoccus neoformans) were explored by the cut plug method and viable cell counting methods.ConclusionsAmine-terminated polyacrylonitrile were used as a novel polymeric carrier for benzaldehyde derivatives as antimicrobial agents. The prepared polymers can inhibit the growth of the microorganisms. The activity was varied according to the tested microorganism as well as the polymer microstructure. It was found that the activity increased with increasing the number phenolic hydroxyl group of the bioactive group. Finally, it is anticipated that the prepared antimicrobial polymers would be of great help in the field of biomedical applications and biological water treatment.

Fabrication of new antifungal polyamide-12 material

Water-resistant polymeric biocide poly(hexamethylene guanidine) dodecylbenzenesulfonate (PHMG-DBS) was synthesized by anion metathesis between poly(hexamethylene guanidine) hydrochloride and sodium dodecylbenzenesulfonate and subsequently characterized using elemental analysis, Raman spectroscopy and thermogravimetric analysis. It is found that PHMG-DBS is thermally stable to at least 350 °C, which makes it suitable for melt blending with polyamide (PA) resins. An antifungal PA-12 composition was prepared by compression moulding of PA-12 and PHMG-DBS powder mixture at 240 °C. The characteristics of the prepared films were investigated: surface roughness and hydrophobicity using atomic force microscopy and contact angle measurements, respectively. No significant change in the material characteristics is observed compared to pure PA-12 films. PA-12 films containing 2 wt% of the PHMG-DBS biocide are found to be highly resistant against Trychophyton mentagrophytes fungus. Copyright © 2012 Society of Chemical Industry

Antimicrobial equipment of poly(isoprene) applying thiol-ene chemistry

The functionalization of anionically polymerized isoprene with cysteamine applying the thiol-ene reaction is reported. Antimicrobial activity is implemented by quaternization of the amino functionality by either alkylation or by protonation. The resulting polymers were tested against Gram-positive as well as Gram-negative bacteria strains according to the Japanese Industrial Standard Z2801:2000 protocol, partly revealing excellent biocidal performance. Thermal stability up to 200°C allows extrusion processing of the functionalized poly(isoprene)s. The best performing polymer, that is, bearing butylated ammonium-groups, was compounded with the commodity material poly(propylene). The compound bearing 5 wt % of the biocidal polymer exhibited satisfactory biocidal properties. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012

Adsorption of cationic polymers on the surfaces of anionic glass microspheres

The adsorption of cationic copolymers prepared by the quaternization of poly(4-vinylpyridine) with bromoacetic acid and/or ethyl bromide on the surface of anionic glass microspheres and the stability of the as-prepared complexes against dissociation in water-salt solutions are studied. Experiments are performed with the use of two types of copolymers: copolymers carrying cationic and hydrophobic units and copolymers carrying cationic and zwitterionic (electroneutral) units in main chains. For hydrophobic copolymers, the limiting adsorption decreases as the molar fraction of cationic groups in the copolymer, α, increases. In the case of hydrophilic copolymers, the dependence of limiting adsorption on α has a bellshaped pattern with a maximum at α = 0.15 and a horizontal segment at α > 0.4. Hydrophobic copolymers feature irreversible binding with microspheres at α > 0.24; hydrophilic copolymers, at α ≥ 0.15. The obtained data may be used for creation of biocidal polymer coatings and sorption layers that reversibly desorb from the surface with a change in the salt concentration in the surrounding aqueous solution.

Synthesis of biocidal polymers containing metal NPs using an electron beam

Metal containing antibacterial polymers were prepared by the polymerization of methylmethacrylate and methacrylic acid with copper or zinc. When the thin film of the polymers coated on a glass was irradiated with an electron beam, nanoparticles were obtained. It was found that these polymers exhibited a potent antibacterial activity against the Gram-negative bacteria, Escherichia coli. The metal containing polymers showed a 99.999% (5.0 logs) reduction in E. coli at a contact time of 12h.In addition, polymers had a good antifouling effect against marine organisms.

Aktualny stan wiedzy o biocydowych polimerach na bazie N-halamin

Aktualny stan wiedzy o biocydowych polimerach na bazie N-halamin

Synthetic, spectroscopic, magnetic, thermal, and antimicrobial approach towards new biocidal coordination polymers

AbstractO‐aminophenol was reacted with glutraldehyde to obtain Schiff base, which was then reacted with formaldehyde in slight acidic medium to generate phenolic groups. Now the substituted Schiff base was reacted with the transition metal acetates of Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) to get polymeric metal complexes. Their structures have been elucidated on the basis of elemental analyses, 1H NMR spectra, 13C NMR spectra, magnetic measurements, thermogravimetric analyses, electronic spectra, and infrared spectra. The results are in accordance with an octahedral environment around the central metal ion. The polychelates of Mn(II), Co(II), Ni(II), and Cu(II) are paramagnetic while Zn(II) polychelate was found to be diamagnetic. The synthesized Schiff base acted as a uninegative bidentate ligand and bonding occurs through the hydroxyl oxygen and nitrogen atoms. The thermal behavior of these coordinating polymers was studied by TGA in nitrogen atmosphere up to the temperature range of 800°C. All the synthesized polychelates were also screened for their biocidal activity against Escherichia coli, Staphylococcus aureus, Bacillus subtilis (bacteria), Candida albicans, and Muller species (yeast) by using agar well diffusion method. All the metal polychelates show promising antimicrobial activities. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci 124:3971–3979, 2012

Interactions of biocidal guanidine hydrochloride polymer analogs with model membranes: a comparative biophysical study

Four synthesized biocidal guanidine hydrochloride polymers with different alkyl chain length, including polyhexamethylene guanidine hydrochloride and its three new analogs, were used to investigate their interactions with phospholipids vesicles mimicking bacterial membrane. Characterization was conducted by using fluorescence dye leakage, isothermal titration calorimetry, and differential scanning calorimetry. The results showed that the gradually lengthened alkyl chain of the polymer increased the biocidal activity, accompanied with the increased dye leakage rate and the increased binding constant and energy change value of polymer-membrane interaction. The polymer-membrane interaction induced the change of pretransition and main phase transition (decreased temperature and increased width) of phospholipids vesicles, suggesting the conformational change in the phospholipids headgroups and disordering in the hydrophobic regions of lipid membranes. The above information revealed that the membrane disruption actions of guanidine hydrochloride polymers are the results of the polymer's strong binding to the phospholipids membrane and the subsequent perturbations of the polar headgroups and hydrophobic core region of the phospholipids membrane. The alkyl chain structure significantly affects the binding constant and energy change value of the polymer-membrane interactions and the perturbation extent of the phospholipids membrane, which lead to the different biocidal activity of the polymer analogs. This work provides important information about the membrane disruption action mechanism of biocidal guanidine hydrochloride polymers.

A simultaneous antimicrobial and shrink resistance treatment of wool woven fabrics using the polymeric biocide polyhexamethylene biguanide

Recently, a novel, effective, and commercially viable antimicrobial treatment for wool was reported that used a peroxymonosulfate/sulfite pretreatment and the biocide polyhexamethylene biguanide (PHMB). Given the polymeric nature of PHMB used in this antimicrobial treatment, this study investigated whether the treatment would also lead to shrink resistance of woven wool fabrics. It was shown that up to 5% PHMB (on mass of fabric) could be exhausted onto the pretreated wool at 40 °C. Under scanning electron microscope, PHMB was observed to coat the wool surface with no obvious interfiber bonding. PHMB finishing was durable to laundering, had little effect on the tensile strength of the fabrics and only slightly increased the bending rigidity. The finishing conferred strong antimicrobial activity to the fabrics and at the same time reduced felting shrinkage after laundering to an acceptable level. Thus, a single finishing process achieved two important functionalities for wool fabrics, antimicrobial activity and shrink resistance.

Biocidal polymers: Synthesis, antimicrobial activity, and possible toxicity of poly (hydroxystyrene‐co‐methylmethacrylate) derivatives

AbstractFunctionalized polymers have gained much interest in the last decades. This is due to their functional group and their polymer nature that give them unique properties and more advantages than the corresponding small molecules. In this trend, polyhydroxystyrene‐co‐MMA was modified to introduce amino group in the side chain of the polymer. The amine modified polymer was reacted with two classes of active compounds. The first class is aldehydes such as vanilline, p‐hydroxybenzaldehyde, p‐chlorobenzaldehyde, and anisaldehyde. The second class is phenolic esters such as p‐hydroxymethylbenzoate, 2,4‐dihydroxymethyl benzoate, and methyl salicylate. The antimicrobial activities of the polymer and modified polymer with these two classes were explored with Gram‐negative bacteria (Escherichia coli), Gram‐positive bacteria (Bacillus subtilus), fugus like yeast (Candida albicans SC5314), and pathogenic molds (Aspergillus flavus, Trycophyton rubrum, and F. oxysporium). In vitro studies indicated that the start polymer did not affect on the test microorganisms, in contrary to its derivatives. The diameter of inhibition zone varied according to the active group in the modified polymer, polymer microstructure, and the test microorganism. Derivatives I, II, and III were selected among the most effective antimicrobial compounds. Their inhibitory effects on the ratio of surviving cell number (M/C) increased by increasing derivatives concentrations. Derivatives I and II were inhibitorier to C. albicans and molds than to bacteria while derivative III was only antibacterial. These derivatives seemed toxic to Brine shrimp by increasing their concentrations above 10 ppm, with derivative III being the less toxic, compared to others. To clarify this toxic effect and to decrease the toxicity of these derivatives, more detailed studies are necessary, and this will be focused in the nearest future. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Contact bactericides and fungicides on the basis of amino‐functionalized poly(norbornene)s

AbstractThis study is aimed at investigating the microbiocidal potential of amino‐functionalized poly(norbornenes) in the solid state. A series of norbornene‐type monomers that carry secondary or tertiary amine functions as well as hexyl and dodecyl groups were prepared. Ring‐opening metathesis polymerization was used to prepare homopolymers of the amine bearing monomers and random copolymers of amine‐ and alkyl‐substituted monomers of high average molar mass. The resulting polymers were characterized by nuclear magnetic resonance, thermogravimetry, differential scanning calorimetry, infrared spectroscopy, and contact angle measurements, and their contact biocidal potential was evaluated according to the Japanese Industry standard Z2801. Tested microorganisms comprised Pseudomonas aeruginosa, Escherichia coli, Staphylococcus aureus, Candida albicans, and Aspergillus niger. Microbiocidal activity of selected polymer films against E. coli, S. aureus, and A. niger was found, whereas against C. albicans and P. aeruginosa microbiostatic behavior was observed. Moreover, the most potent copolymer revealed no cytotoxicity rendering a biocidal polymer with potential applications in mammalian‐, and in particular, human‐related fields. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010

Photocatalytic Antibacterial Capabilities of TiO2−Biocidal Polymer Nanocomposites Synthesized by a Surface-Initiated Photopolymerization

Novel biocidal polymer-functionalized TiO(2) nanoparticles were prepared by surface-initiated photopolymerization using titania as an initiator. Vinyl monomer mixtures of nontoxic secondary amine-containing biocidal 2-(tert-butylamino)ethyl methacrylate and antifouling ethylene glycol dimethacrylate were used for the antimicrobial polymer shell. It was shown that the synthesized TiO(2)/poly[2-(tert-butylamino)ethyl methacrylate-co-ethylene glycol dimethacrylate] core/shell nanoparticles had enhanced photocatalytic antibacterial properties compared to the pristine TiO(2) nanoparticles due to the combined antibacterial activities of light-driven anti-infective TiO(2) core and biocidal polymer shell. In the dark condition, the TiO(2)/biocidal polymer nanoparticles exhibited high antimicrobial efficiency (95.7%) against gram-positive S. aureus. Furthermore, during UV irradiation, the TiO(2)/biocidal polymer showed improved inhibition of bacterial growth against gram-negative E. coli and gram-positive S. aureus in comparison to the pristine TiO(2) nanoparticles.

Macroscopic N‐halamine biocidal polymeric beads

AbstractThe particle size of N‐halamine biocidal polymers was methodically modified forming beads of different sizes by blending water‐insoluble N‐halamine polyurethane with sodium alginate as the matrix and loading heterocyclic rings onto modified silica gels. The biological activity of the prepared beads and halogenated modified silica derivatives was evaluated against examples of Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli) bacteria. The recycling possibilities and the optimum preparation conditions of the blended beads were investigated; blending prehalogenated polyurethane (5%, w/v) with sodium alginate (3%, w/v) followed by crosslinking with CaCl2 (10%, w/v) at 40°C are the optimum preparation conditions for the alginate beads. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

Optimizing halogenation conditions of N‐halamine polymers and investigating mode of bactericidal action

AbstractAn N‐Halamine biocidal polymer was prepared by co‐polymerizing toluene‐2,6‐diisocyanate with a new heterocyclic uramil‐based azo‐monomer, followed by halogenation. The mode of action of N‐halamine polymers on bacteria was investigated and halogenation conditions (temperature, halogenation time, halogen concentration) were optimized for bactericidal action against E. coli and S. aureus. It was found that the mode of action of this type of polymer is a combination of different factors; contact, release, and through interaction of the polymer with the bacterial medium. The most effective halogenation conditions were stirring 1 g polymer in 10 mL sodium hypochlorite (10 %) for 1 h at ambient temperature (22°C). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009

The role of hydrophobicity in the antimicrobial and hemolytic activities of polymethacrylate derivatives.

We synthesized cationic random amphiphilic copolymers by radical copolymerization of methacrylate monomers with cationic or hydrophobic groups and evaluated their antimicrobial and hemolytic activities. The nature of the hydrophobic groups, and polymer composition and length were systematically varied to investigate how structural parameters affect polymer activity. This allowed us to obtain the optimal composition of polymers suitable to act as non-toxic antimicrobials as well as non-selective polymeric biocides. The antimicrobial activity depends sigmoidally on the mole fraction of hydrophobic groups (f(HB)). The hemolytic activity increases as f(HB) increases and levels off at high values of f(HB), especially for the high-molecular-weight polymers. Plots of HC(50) values versus the number of hydrophobic side chains in a polymer chain for each polymer series showed a good correlation and linear relationship in the log-log plots. We also developed a theoretical model to analyze the hemolytic activity of polymers and demonstrated that the hemolytic activity can be described as a balance of membrane binding of polymers through partitioning of hydrophobic side chains into lipid layers and the hydrophobic collapsing of polymer chains. The study on the membrane binding of dye-labeled polymers to large, unilamellar vesicles showed that the hydrophobicity of polymers enhances their binding to lipid bilayers and induces collapse of the polymer chain in solution, reducing the apparent affinity of polymers for the membranes.

Acyclic halamine polypropylene polymer: Effect of monomer structure on grafting efficiency, stability and biocidal activities

Radical graft polymerization of polypropylene (PP) with acrylic amide derivatives was studied in a melt extrusion process. Fourier transform spectroscopy (FTIR) results and nitrogen analysis confirmed that acrylamide (AAM), methacrylamide (MAM), N-tert-butylacrylamide (NTAAM) and N-tert-butylmethacrylamide (NTMAM) were successfully grafted onto PP, and the grafted products were employed as precursors of biocidal N-halamine polymers. Monomer structures affected grafting efficiency and polymer chain scission reactions on the polymer. Addition of styrene (St) as a co-monomer in the grafting process was studied. Addition of St significantly prevented polymer chain scission, though, could increase or decrease grafting content of vinyl-amide monomers. The reactivity ratios of the multi-monomer systems during melt-grafting process were evaluated through Fineman–Ross method. The halogenated products exhibited powerful antimicrobial properties against Escherichia coli and Staphylococcus aureus. In addition, the possible hydrolysis mechanism of acyclic N-halamine polymers during several recharging cycles were proposed based on experimental data.

Durable and rechargeable biocidal polypropylene polymers and fibers prepared by using reactive extrusion

Incorporation of N-halamine precursor onto polypropylene was explored by using a reactive extrusion process. Several cyclic and acyclic halamine precursors were grafted onto polypropylene backbone through a melt free radical graft copolymerization. The structures and morphology of the grafted polymer were characterized with FTIR, and scanning electron microscope. Thermal properties of the polymers were evaluated by differential scanning calorimetry. The halogenated products of the corresponding grafted samples exhibited potent antimicrobial properties against Escherichia coli, and the antimicrobial properties were durable and regenerable. The relationship between effective surface contact and biocidal efficacy are further discussed.

Biocidal polymers (II): Determination of biological activity of novel N-halamine biocidal polymers and evaluation for use in water filters

Novel N-halamine biocidal polymers were prepared by co-polymerizing a heterocyclic ring-based monomer with tolylene-2,6-diisocyanate and toluene-2,4-diisocyanate. The resulting polyurethanes were halogenated; chlorinated, brominated or iodinated. The rate of bacterial killing by the halogenated derivatives was determined both with and without halogen quenching and one of them was evaluated for use in water filters. The effect of these polymers on bacterial growth-rates was also determined.