Quaternary Ammonium Polyethyleneimine Research Articles

Antimicrobial Efficacy of Various Nanoparticles on Addition to Orthodontic Materials- A Systematic Review and Meta-Analysis

Aim: The purpose of this study is to examine the evidence for the efficiency of nanoparticles (NPs) incorporated into orthodontic materials (brackets, bonding agents, wires, acrylic resin, and elastics) in order to enhance their antimicrobial properties. Materials and Methods: A comprehensive search strategy was conducted in electronic databases like PubMed, Cochrane, and Google scholar, books, grey literature like unpublished literature, dissertations, conference reports, etc. Finally, out of all the literature reviewed, a total of 30 articles met the inclusion criteria and were included in the qualitative analysis. For the quantitative analysis, a total of 6 articles were used. Results: Antimicrobial agents such as silver nanoparticles, Titanium dioxide, Silver platinum alloy, zinc oxide and copper oxide, quaternary ammonium dimethacrylate (QADM), Hydroxyapatite crystals, and silver, quaternary ammonium polyethyleneimine (QPEI) particles, silica, and titanium have been incorporated in various orthodontic materials. The incorporation of these nanoparticles into orthodontic materials led to a significant increase in the antibacterial capacity when compared to controls used in the various studies. Conclusion: It can be concluded that the incorporation of nanoparticles into orthodontic materials improves their antibacterial properties. Due to the heterogeneity observed across the studies reviewed, further research with standardized study protocols in terms of the size, concentration, and techniques of incorporation of different NPs into various orthodontic materials is pertinent.

Mussel-inspired surface modification of urinary catheters with both zwitterionic and bactericidal properties for effectively preventing catheter-associated infection

Catheter-associated urinary tract infections (CAUTIs), caused by rapid bacterial colonization and biofilm formation on urinary catheters (UCs), are one of the most common hospital-acquired infections. To address this challenge, introducing non-leaching contact-killing bactericidal and antifouling functions on UCs becomes an attractive way to prevent infections. However, current surface strategies for UCs still have limitations, such as the weakening bactericidal/antifouling activities due to competition between diverse components, and complex preparation procedures. Herein, we report a facile and effective surface modification strategy for commercial UC by organic integration of contact-killing and antifouling functionalities to combat biofilm formation. In this proposal, amino-rich quaternary ammonium polyethyleneimine (QPEI) was selected as a bactericidal linker to react covalently with both adhesive dopamine (DA) and antifouling component of poly(carboxylbetaine-co-dopamine methacrylamide) copolymer (pCBDA) via mussel-inspired chemistry, resulting in robust co-deposition of a hydrophilic and uniform polymeric coating (defined as QCB) onto commercial UC surface. The well-designed QCB coating endows modified surface the ability to not only efficiently resist the attachment of bacteria (bacterial antiadhesion rate: > 99.5 %), but also maintain remarkable bactericidal property of QPEI (kill efficiency: > 99.9 %), thereby preventing biofilm formation even after daily exposure to the bacteria-contacting environment over 30 days. More importantly, QCB-coated UC performed an excellent anti-infective activity in vivo using urinary tract infection rabbit models. Meanwhile, a low level of inflammatory response in vivo suggested good biocompatibility of QCB coating. It is envisioned that the QCB coating will provide a promising solution for UC to address CAUTIs.

Antibacterial performance of composite containing quaternary ammonium silica (QASi) filler – A preliminary study

BackgroundAntibacterial composite will have a significant clinical advantage in controlling caries. This study tests the antibacterial properties of a novel bulk-fill flowable composite (Infinx™, Nobio™ Ltd.) containing quaternary ammonium silica (QASi) filler particles. MethodsInfinix™ was tested in-vitro by the direct contact test (DCT), using E. faecalis or whole saliva as inoculum. A similar formula composite without QASi served as a control. In addition, composite test samples were polymerized on three volunteers' intact buccal enamel surfaces of mandibular first premolars in a split-mouth design experiment. Traditional composite served as control (Filtek Bulk Fill Flowable, 3M). Bacterial viability on the composite surfaces weres assessed ex-vivo microscopically six months later, using a fluorescent dead/live stain. Images of each bacterial sample were taken using a fluorescent microscope (Nikon Eclipse 80i), and further live/total cell analysis was performed using ImageJ software. ResultsFollowing direct contact with one week of aged Infinix, more than 1 million E. faecalis bacteria were killed. Similarly, when using the saliva as inoculum, no single microorganism survived. Six-month in-vivo experiments supported these results by showing a reduction of 54%, 30% and 28% in live/total number of bacteria ratio retrieved from antibacterial composite vs. the control in volunteers #1, #2, #3 respectively. ConclusionWithin the limitations of the experimental design, the present study suggest that antibacterial activity of quaternary ammonium silica particles (QASi) is comparable to that of previously described quaternary ammonium polyethyleneimine particles (QPEI). In addition, whole saliva bacteria are effectively killed by QASi-containing composite in-vitro and in-vivo, for a period of six month at least. Long-term full-scale clinical study is needed to confirm the findings of the present study and their implication on maintaining health balance. Clinical significance: Antibacterial composites containing QASi filler is a novel class of restoratives that may contributes to caries lesion control.

Functionalized Silver Nanocapsules with Improved Antibacterial Activity Using Silica Shells Modified with Quaternary Ammonium Polyethyleneimine as a Bacterial Cell-Targeting Agent.

Silver nanoparticles (AgNPs) have remarkable and broad-spectrum antibacterial activities against Gram-positive (G+) and Gram-negative bacteria (G-). However, the negative surface potential of AgNPs limits their antibacterial activities due to the electrostatic repulsion with the negatively charged bacterial cell membrane. To address the limitation, AgNPs were loaded in the mesoporous silica nanoparticles by preparing silver core-mesoporous silica shell nanocapsules (Ag@MSNs), and then, a cationic antibacterial polymer, quaternary ammonium polyethyleneimine (QPEI), was used to modify Ag@MSNs for improving their surface potential and antibacterial activities. The results showed that the obtained Ag@MSN-QPEI exhibited a high positive surface potential (+39.6 mV) and a strong electrostatic attraction with Pseudomonas syringae pv. lachrymans cells in coculture, resulting in an excellent bacterial cell-targeting effect. At the same concentration, Ag@MSN-QPEI exhibited less silver content (reducing the silver content of Ag@MSNs by 19%), higher antibacterial activities, and longer effective duration against Clavibacter michiganensis subsp. michiganensis (G+) and P. syringae pv. lachrymans (G-) than Ag@MSNs and QPEI alone. The excellent bacterial cell-targeting effect and synergistic antibacterial action combined with QPEI accounted for the significantly enhanced antibacterial activities of Ag@MSN-QPEI. Therefore, using a cationic antibacterial polymer to confer the bacterial cell-targeting effect and synergistic antibacterial action would be extended to other antimicrobial materials.

Surface-modified nanoparticles as anti-biofilm filler for dental polymers.

The objective of the study was to synthesis silica nanoparticles modified with (i) a tertiary amine bearing two t-cinnamaldehyde substituents or (ii) dimethyl-octyl ammonium, alongside the well-studied quaternary ammonium polyethyleneimine nanoparticles. These were to be evaluated for their chemical and mechanical properties, as well for antibacterial and antibiofilm activity. Samples were incorporated in commercial dental resin material and the degree of monomer conversion, mechanical strength, and water contact angle were tested to characterize the effect of the nanoparticles on resin material. Antibacterial activity was evaluated with the direct contact test and the biofilm inhibition test against Streptococcus mutans. Addition of cinnamaldehyde-modified particles preserved the degree of conversion and compressive strength of the base material and increased surface hydrophobicity. Quaternary ammonium functional groups led to a decrease in the degree of conversion and to low compressive strength, without altering the hydrophilic nature of the base material. In the direct contact test and the anti-biofilm test, the polyethyleneimine particles exhibited the strongest antibacterial effect. The cinnamaldehyde-modified particles displayed antibiofilm activity, silica particles with quaternary ammonium were ineffective. Immobilization of t-cinnamaldehyde onto a solid surface via amine linkers provided a better alternative to the well-known quaternary ammonium bactericides.

Dual antimicrobial effects induced by hydrogel incorporated with UV-curable quaternary ammonium polyethyleneimine and AgNO3

This study presents a simple method for fabricating a highly potent dual effect antibacterial hydrogel consisting of a UV-curable cationic polyethyleneimine (QUV-PEI) and embedded silver nitrate (AgNO3). In the first part of this study, polyethyleneimine (PEI) was reacted with 3-(acryloyloxy)-2-hydroxypropyl methacrylate (ACOM) to introduce methacryl functionality onto the backbone. UV-curable PEI was further quaternized by N-methylation with methyl iodate. Hydrogels based on QUV-PEI and AgNO3were found to have impressive biocidal properties. The antibacterial properties were assessed by spraying aqueous suspensions of bacterial cells on the surface, followed by air drying and counting the number of remaining viable cells (i.e. capable of growing into colonies). In a manner depending on the QUV-PEI content in the gel formulation, up to 99±1% of Escherichia coli and Staphylococcus aureus cells sprayed on the resulting hydrogel surfaces were killed. The inclusion of AgNO3 in the QUV-PEI based hydrogel not only enhanced the antimicrobial property against adherent bacteria but also led to the inhibition of bacterial growth in suspended culture via the long-term release of Ag/Ag+ to the surrounding media. Cytotoxicity studies on human umbilical vein endothelial cells and MTS cell lines were also performed with hydrogels. These findings confirm that hydrogels are potentially useful as antimicrobial agents in a wide variety of applications.

Antibacterial effect of composite resin foundation material incorporating quaternary ammonium polyethyleneimine nanoparticles

Statement of problemAs caries is the most frequent cause of the failure of composite resin-based restorations, composite resins with antibacterial properties are desirable. However, whether quaternary ammonium polyethyleneimine nanoparticles can be effectively incorporated is unknown. PurposeThe purpose of this in vitro study was to evaluate the antibacterial activity against Streptococcus mutans and Actinomyces viscosus of a foundation material incorporating quaternary ammonium polyethyleneimine (QPEI) nanoparticles. Material and methodsQPEI antimicrobial nanoparticles were incorporated in a commercially available foundation material (Q Core; BJM Laboratories Ltd) at 1% wt/wt. Antibacterial efficacy against S mutans (106 colony-forming units [CFU]/mL) and A viscosus (106 CFU/mL) was examined by the direct contact test (DCT), and the agar diffusion test (ADT) with and without surface polishing. Bacterial outgrowth was recorded with a spectrophotometer. ResultsGrowth of S mutans and A viscosus was inhibited, showing a decrease by 6 orders of magnitude in bacterial viability in specimens incorporating the nanoparticles, even after polishing the foundation material (P<.05). Growth inhibition was not observed in specimens without nanoparticles. ConclusionsAntibacterial properties can be achieved in a commercially available foundation material by incorporating polycationic antibacterial nanoparticles. This antibacterial effect did not diminish after surface polishing.

Synthesis variants of quaternary ammonium polyethyleneimine nanoparticles and their antibacterial efficacy in dental materials.

Resin-based dental materials allow bacterial growth on their surface and lack antibacterial activity, leading to functional and esthetic failure. Quaternary ammonium polyethyleneimine (QPEI) nanoparticles (NPs) incorporated in resin-based composite at 2% wt/wt have demonstrated prolonged and complete inhibition of bacterial growth. This study focused on optimization of QPEI NP synthesis to reduce the concentration required for bacterial growth inhibition. The objective here was to enhance antimicrobial efficacy by excess base neutralization, using phosphoric or hydrochloric acid, and by using surfactants. QPEI NP variants were prepared (i) under controlled neutralization of acid, using NaHCO3, (ii) under controlled carbonate ion neutralization with HCl or H3PO4 and (iii) by treatment with N-lauroylsarcosine or glycerol monostearate. NPs incorporated in the dental materials were examined for their antibacterial effect against Enterococcus faecalis. Controlled addition of NaHCO3 resulted in modified QPEI NPs with an increased ability to inhibit bacterial growth. Surface treatment with N-lauroylsarcosine resulted in enhanced antibacterial activity at 0.5% wt/wt concentration in acrylate and epoxy resin-based dental materials. The antimicrobial efficacy of QPEI NP may be improved significantly by controlling the addition of NaHCO3, neutralization of excess base and the surface-agent effect.

Antimicrobial evaluation of quaternary ammonium polyethyleneimine nanoparticles against clinical isolates of pathogenic bacteria.

Peritonitis is a disease caused by bacterial strains that have become increasingly resistant to many antibiotics. The development of alternative therapeutic compounds is the focus of extensive research, so novel nanoparticles (NPs) with activity against antibiotic-resistant bacteria should be developed. In this study, the antibacterial activity of quaternary ammonium polyethyleneimine (QA-PEI) NPs was evaluated against Streptococcus viridans, Stenotrophomonas maltophilia and Escherichia coli. To appraise the antibacterial activity, minimal inhibitory concentration (MIC), minimal bactericidal concentration and bactericidal assays were utilised with different concentrations (1.56-100 µg/ml) of QA-PEI NPs. Moreover, 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MTT) and annexin V/propidium iodide toxicity assays were performed in cell cultures. MICs for S. maltophilia and E. coli isolates were 12.5 and 25 µg/ml, respectively, whereas the MIC for S. viridans was 100 µg/ml. Furthermore, the growth curve assays revealed that these QA-PEI NPs at a concentration of 12.5 µg/ml significantly inhibited bacterial growth for the bacterial isolates studied. On the other hand, QA-PEI NPs lacked significant toxicity for cells when used at concentrations up to 50 μg/ml for 48 h. The present findings reveal the potential therapeutic value of this QA-PEI NPs as alternative antibacterial agents for peritonitis, especially against Gram-negative bacteria.

Lethal bacterial trap: Cationic surface for endodontic sealing.

Insoluble antibacterial cationic nanoparticles have been previously shown to have potent and long-lasting antibacterial properties. Our tested hypothesis was that root canal pathogens will be attracted to and eliminated when exposed to epoxy resin-based surfaces incorporating cationic nanoparticles. In our research, an epoxy resin-based surface incorporating quaternary ammonium polyethyleneimine (QPEI) nanoparticles was evaluated. Surface characterization was performed using atomic force microscopy and X-ray photoelectron spectra. The surface anti-Enterococcus faecalis effect was evaluated in an anti-gravitational model. Cell membrane potential, viability, biofilm thickness, and biomass were tested using flow cytometry and confocal laser scanning microscopy. Additionally, the antibiofilm activity of the bacterial supernatant was assessed. The surface characterization showed QPEI nanoparticle embedment on the modified sealer. The epoxy resin-based surface incorporating the QPEI nanoparticles actively attracted bacteria, causing membrane destabilization, and bacterial death. The supernatant of bacteria pre-exposed to QPEI showed an antibacterial effect. In conclusion, the tested epoxy resin-based surface incorporating QPEI nanoparticles traps and kills bacteria. The nanoparticles attracted bacteria, reducing their viability, and promoting cell death.

Intratubular Antibacterial Effect of Polyethyleneimine Nanoparticles: An Ex Vivo Study in Human Teeth

Enterococcus faecalis is a facultative gram positive bacterium which can remain in the teeth root canals and cause refractory or persistent periapical diseases. E. faecalis bacteria that penetrate the dentinal tubules can be the source of intracanal infection and endodontic disease. Quaternary ammonium polyethyleneimine (QPEI) nanopolymers were shown to have long lasting antibacterial activity against gram positive and gram negative bacteria. The present study evaluated the intratubular antibacterial effect of an epoxy resin sealer incorporating 1% QPEI against E. faecalis in a human dentin model. Root canals of extracted teeth were inoculated with E. faecalis for 7 days prior to standard endodontic treatment. The antibacterial effect of an epoxy‐amine resin endodontic sealer was tested at concentration of 0% or 1% (wt/wt) added QPEI nanoparticles. Reduction in bacterial viability (p &lt; 0.01) was depicted in the dentinal tubules of the root canals obturated with the sealer incorporating QPEI nanoparticles. In conclusion, QPEI nanoparticles when incorporated in a small percentage into epoxy‐resin based sealer may target E. faecalis in the dentinal tubules, producing a potent antibacterial effect that reduces significantly bacterial viability.

Antimicrobial silica particles loaded with quaternary ammonium polyethyleneimine network

Silica particles functionalized with quaternary ammonium groups were prepared by interpenetrating polyethylenimine (PEI) into silica particles and crosslinking with diiodopentane, followed by octyliodide alkylation and methyliodide quaternarization (S‐QA‐PEI). The synthesized S‐QA‐PEI particles were identified with a slight particle size increase of 2–3 µm. Different ratios of PEI:silica particles were prepared and analyzed. While silica particles are negatively charged, −16.7 ± 5.11 mV, the prepared S‐QA‐PEI particles are positively charged, +50–60 mV. These particles were embedded in poly(ethylene vinyl acetate) and poly(ethylene methacrylic acid) coatings which exhibited strong antibacterial activity. Copyright © 2014 John Wiley &amp; Sons, Ltd.

Antibacterial activity of bone cement containing quaternary ammonium polyethyleneimine nanoparticles

Antibacterial activity of bone cement containing quaternary ammonium polyethyleneimine nanoparticles

Antibacterial temporary restorative materials incorporating polyethyleneimine nanoparticles.

Temporary restorative materials (TRMs) often rapidly lose their dimensional stability and antibacterial properties after exposure to humidity and bacterial infection. Quaternary ammonium polyethyleneimine (QPEI) nanoparticles (NP) are long-lasting, stable, biocompatible, and nonvolatile antibacterial polymers. In the present study, we incorporated QPEI NP into standard TRMs and examined their influence on dimensional stability and their ability to reduce bacterial leakage. A modified split-chamber model was used in vitro to test calcium sulfate-based and zinc oxide-eugenol- based TRMs (Coltosol and IRM, respectively). Both materials were tested with and without 2% wt/wt incorporated QPEI NP for fluid and bacterial leakage. The calcium sulfate-based TRM displayed the lowest microleakage and highest antibacterial resistance. Two-way A NOVA analysis of the fluid transport test results showed that incorporation of 2% wt/wt QPEI NP significantly increased the sealing ability of both TRMs (P < .01). Analysis of survival curves by the Kaplan-Meier method showed that the calcium sulfate-based TRM with 2% wt/wt QPEI NP survived the bacterial load significantly more effectively than did the zinc oxide-eugenol-based TRM (P < .0001). Incorporation of 2% w/w QPEI NP may prominently improve the sealability and the antibacterial properties of TRMs. TRMs incorporating antibacterial nanoparticles may be clinically advantageous for sealing the endodontic access cavity to avoid reinfection of the root canal system during endodontic treatment.

QUATERNARY AMMONIUM ANTIMICROBIAL POLYMERS

ABSTRACTPolymers possessing antimicrobial activity have been used for self sterilization surfaces as well as agents for treating contaminated water. Cationic polymers based on quaternary ammonium or guanidine groups have shown high inherent antimicrobial activity where the activity is related to the disruption of the microorganism cell wall. A range of antimicrobial nanoparticles possessing active quaternary ammonium groups with one of the alkyl is a an octyl chain have been synthesized. These nanoparticles were incorporated in dental restoration compositions to form self sterile composites. Quaternary ammonium polyethyleneimine nanoparticles with N-octyl dimethyl residues, demonstrated high antibacterial effect.

Quaternary Ammonium Polyethyleneimine: Antibacterial Activity

Quaternary ammonium polyethyleneimine‐ (QA‐PEI‐) based nanoparticles were synthesized using two synthetic methods, reductive amination and N‐alkylation. According to the first method, QA‐PEI nanoparticles were synthesized by cross‐linking with glutaraldehyde followed by reductive amination with octanal and further N‐methylation with methyl iodide. The second method is based on crosslinking with dialkyl halide followed by N‐alkylation with octyl halide and further N‐methylation with methyl iodide. QA‐PEI nanoparticles completely inhibited bacterial growth (&gt;106 bacteria), including both Gram‐positive, that is, Staphylococcus aureus at 80 μg/mL, and Gram‐negative, that is, Escherichia coli at 320 μg/mL. Activity analysis revealed that the degree of alkylation and N‐methylation of the QA‐PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl alkylated QA‐PEI alkylated at 1 : 1 mole ratio (primary amine of PEI monomer units/alkylating agent). Also, cytotoxicity studies on MAT‐LyLu and MBT cell lines were performed with QA‐PEI nanoparticles. These findings confirm previous reports that polycations bearing quaternary ammonium moieties inhibit bacterial growth in vitro and have a potential use as additives in medical devices which need antibacterial properties.

Antibacterial effect of composite resins containing quaternary ammonium polyethyleneimine nanoparticles

Quaternary ammonium polyethyleneimine (QA-PEI)-based nanoparticles were synthesized by crosslinking with dibromopentane followed by N-alkylation with various alkyl halides and further N-methylation with methyl iodide. Insoluble pyridinium-type particles were prepared by suspension polymerization of 4-vinyl pyridine followed by N-alkylation with alkyl halides. Polyamine-based nanoparticles embedded in restorative composite resin at 1% w/w were tested for antibacterial activity against Streptococcus mutans using direct contact test. Activity analysis revealed that the alkyl chain length of the QA-PEI nanoparticles plays a significant role in antibacterial activity of the reagent. The most potent compound was octyl-alkylated QA-PEI embedded in restorative composite resin at 1% w/w that totally inhibited S. mutans growth in 3-month-aged samples. This data indicates that restorative composite resin with antibacterial properties can be produced by the incorporation of QA-PEI nanoparticles.

Germ warfare.

Research ArticleOpen AccessGerm warfare. J Medlin J Medlin Search for more papers by this author Published:1 March 1997https://doi.org/10.1289/ehp.97105290Cited by:11AboutSectionsPDF ToolsDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InReddit FiguresReferencesRelatedDetailsCited by ZHANG Y, CHEN Y, HU Y, HUANG F and XIAO Y (2018) Quaternary ammonium compounds in dental restorative materials, Dental Materials Journal, 10.4012/dmj.2017-096, 37:2, (183-191), . Rodríguez-Hernández J (2017) Antimicrobial/Antifouling Surfaces Obtained by Surface Modification Polymers against Microorganisms, 10.1007/978-3-319-47961-3_5, (95-123), . Alfredo N and Rodríguez-Hernández J (2017) Antimicrobial Polymeric Nanostructures Nanostructures for Antimicrobial Therapy, 10.1016/B978-0-323-46152-8.00004-4, (85-115), . Taylor M, McCollister B and Park D (2015) Highly Bactericidal Polyurethane Effective Against Both Normal and Drug-Resistant Bacteria: Potential Use as an Air Filter Coating, Applied Biochemistry and Biotechnology, 10.1007/s12010-015-1928-0, 178:5, (1053-1067), Online publication date: 1-Mar-2016. Rodríguez-Hernández J (2016) Antimicrobial micro/nanostructured functional polymer surfaces Nanobiomaterials in Antimicrobial Therapy, 10.1016/B978-0-323-42864-4.00005-1, (153-192), . Pietrokovski Y, Nisimov I, Kesler-Shvero D, Zaltsman N and Beyth N (2016) Antibacterial effect of composite resin foundation material incorporating quaternary ammonium polyethyleneimine nanoparticles, The Journal of Prosthetic Dentistry, 10.1016/j.prosdent.2016.02.022, 116:4, (603-609), Online publication date: 1-Oct-2016. Wynne K, Kurt P, Brunson K, Chakravorty A, Gupta M, Zhang W, Wood L and Ohman D (2013) Health and Safety via Surface Modification of Polyurethanes Tailored Polymer Architectures for Pharmaceutical and Biomedical Applications, 10.1021/bk-2013-1135.ch018, (303-318), Online publication date: 1-Jan-2013. RODRIGUES D, TEIXEIRA P, OLIVEIRA R and AZEREDO J (2011) Salmonella enterica Enteritidis Biofilm Formation and Viability on Regular and Triclosan-Impregnated Bench Cover Materials, Journal of Food Protection, 10.4315/0362-028X.JFP-10-167, 74:1, (32-37), Online publication date: 1-Jan-2011. Grunzinger S, Kurt P, Brunson K, Wood L, Ohman D and Wynne K (2007) Biocidal activity of hydantoin-containing polyurethane polymeric surface modifiers, Polymer, 10.1016/j.polymer.2007.06.010, 48:16, (4653-4662), Online publication date: 1-Jul-2007. Cen L, Neoh K and Kang E (2004) Antibacterial activity of cloth functionalized with N-alkylated poly(4-vinylpyridine), Journal of Biomedical Materials Research, 10.1002/jbm.a.30125, 71A:1, (70-80), Online publication date: 1-Oct-2004. Tiller J, Lee S, Lewis K and Klibanov A (2002) Polymer surfaces derivatized with poly(vinyl-N-hexylpyridinium) kill airborne and waterborne bacteria, Biotechnology and Bioengineering, 10.1002/bit.10299, 79:4, (465-471), Online publication date: 20-Aug-2002. Vol. 105, No. 3 March 1997Metrics About Article Metrics Publication History Originally published1 March 1997Published in print1 March 1997 Financial disclosuresPDF download License information EHP is an open-access journal published with support from the National Institute of Environmental Health Sciences, National Institutes of Health. All content is public domain unless otherwise noted. Note to readers with disabilities EHP strives to ensure that all journal content is accessible to all readers. However, some figures and Supplemental Material published in EHP articles may not conform to 508 standards due to the complexity of the information being presented. If you need assistance accessing journal content, please contact [email protected]. Our staff will work with you to assess and meet your accessibility needs within 3 working days.