Polyhexamethylene Guanidine Hydrochloride Research Articles

Permanent antimicrobial cotton fabrics obtained by surface treatment with modified guanidine

Antimicrobial cotton fabrics received much attention for the demand of health and hygiene fields. In this work, an antimicrobial copolymer was prepared via a reaction between polyhexamethylene guanidine hydrochloride and polypropylene glycol diglycidyl ether. The copolymer has amphiphilic characteristic and excellent antimicrobial properties. When the copolymer was adhered onto cotton fabrics through physical adsorption and chemical bonding using dipping-drying method, the resultant cotton fabrics had excellent and durable antimicrobial properties. The antimicrobial rates against Escherichia coli and Staphylococcus aureus were higher than 99.99% when the adsorption amount of the copolymer was above 35.5mg/g. The antimicrobial cotton fabrics remained the excellent antimicrobial properties even after laundered with detergent solution.

Antimicrobial paper obtained by dip-coating with modified guanidine-based particle aqueous dispersion

Nonbiodegradable features and the lack of antimicrobial activity for conventional synthetic polymer-based packaging materials remain as extensive concerns for environmental issues and food safety. In this work, an antimicrobial copolymer PHGH–PPGDE was synthesized via a reaction between polyhexamethylene guanidine hydrochloride (PHGH) and poly(propylene glycol)diglycidyl ether (PPGDE). The obtained PHGH–PPGDE was amphiphilic, antimicrobial and reactive due to the terminal reactive group. The TEM images indicated that PHGH–PPGDE formed aggregated particles dispersed in water. The antimicrobial paper was conveniently prepared by dip-coating a paper matrix in the PHGH–PPGDE aqueous dispersion, or mixing the dispersion with pulp. The resultant paper showed excellent antimicrobial activities against Escherichia coli and improved durability for the nonleaching effect.

Formation of leather biostability with the use of cationic polyelectrolytes

The creation of new preparations with a wide range of biocidal action on the pathogenic microorganisms, long-term protective action and, at the same time, with low toxicity for humans and safe for the environment, is a relevant direction in the development of modern technologies in the production of leather materials. In the present article we report the results of examining the antibacterial properties of leather, modified with a composition of natural minerals (zeolite, montmorillonite) and polyhexamethyleneguanidine hydrochloride (PHMG-HC) – cationic polyelectrolyte. PHMG-HC is related to the biocides with a wide range of antimicrobial action, it provides surfaces that are treated with a long-lasting bactericidal effect (up to 8 months), which is why it is called a unique biocide with prolonged action. However, up to now, the use of PHMG-HC to provide leather materials with anti-bacterial properties has not been explored. The research was conducted using the lining leather, impregnated with the dispersed solutions of zeolite and montmorillonite. The modification of leather with PHMG-HC, the substance included in the register of preparations permitted by the EU, was carried out at the stage of after-tanning processes in the production of leather. We propose to use the preparation as a polyfunctional material that fixes the filling and greasing materials in the dermis structure and simultaneously provides it with antibacterial properties. As a result of research, we established special features of the anti-bacterial properties of leather depending on the treatment of a semi-finished product with the solutions of PHMG-HC at different concentration and the type of mineral filler. It is shown that the examined samples acquire a certain level of biostability when treated with the solution of PHMG-HC at concentration not lower than 2.5 %. It is determined that the structure of natural minerals and their location in the leather dermis affect the degree of absorption of the biocide by a semi-finished product. It was found that the leather materials, modified with PHMG-HC, exert a pronounced bactericidal effect on the bacteria of the genus Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis. Research results demonstrated the possibility of obtaining leather materials with special antibacterial properties when using environmentally safe biocidal preparation (polyhexamethyleneguanidine hydrochloride) and accessible and cheap natural minerals (zeolite, montmorillonite).

Synthesis, Characterization, and Bactericidal Evaluation of Chitosan/Guanidine Functionalized Graphene Oxide Composites.

In response to the wide spread of microbial contamination induced by bacterial pathogens, the development of novel materials with excellent antibacterial activity is of great interest. In this study, novel antibacterial chitosan (CS) and polyhexamethylene guanidine hydrochloride (PHGC) dual-polymer-functionalized graphene oxide (GO) (GO-CS-PHGC) composites were designed and easily fabricated. The as-prepared materials were characterized by Fourier transform infrared (FTIR), X-ray photoelectron spectrometer (XPS), field emission scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), thermogravimetric analysis (TGA) and Raman spectroscopy. Their antibacterial capability towards bacterial strains was also studied by incubating both Gram-negative bacteria and Gram-positive bacteria in their presence. More significantly, the synergistic antibacterial action of the three components was assayed, and the findings implied that the as-prepared GO-CS-PHGC shows enhanced antibacterial activity when compared to its single components (GO, CS, PHGC or CS-PHGC) and the mixture of individual components. Not only Gram-negative bacteria but also Gram-positive bacteria are greatly inhibited by GO-CS-PHGC composites. The minimum inhibitory concentration (MIC) value of GO-CS-PHGC against E. coli was 32 μg/mL. With the powerful antibacterial activity as well as its low cost and facile preparation, GO-CS-PHGC has potential applications as a novel antibacterial agent in a wide range of biomedical uses.

ранозаживляющее действие гидрогеля на основе полигуанидинов

This article present the evaluation of polyhexamethyleneguanidine hydrochloride hydrogel influence on the course of wound healing processes. Synthesis of hydrogel is based on the interaction of amino-end groups of the polymer with carbonyl compounds. The presence of significant biocidal properties of the gel-forming polymer is allowed to consider the hydrogel as a wound healing agent. Since most wound healing agents for external use are made in the form of gels, ointments, poly-mer-based, it was decided to use the wound healing agent “Levomekol”, a gel which consists of poly (ethylene oxide) as a comparison drug. So, in terms of linear skin-muscle wound we established the pronounced wound-healing effect of a polyhexamethyleneguanidine hydrochloride hydrogel. The results of pathomorphological studies revealed that in animals of the experimental “hydrogel” group on the eighth day of the experiment, the wound was undergoing a process of rejection of the scab, the presence of mature granulation tissue and no exudate was also observed. In the comparison group, the healing process was more slow, on the eighth day of the experiment in the animal group we observed the presence of fluid under the eschar, and lower amount of mature granulation tissue. Tensiometry of the scar has shown that the strength of scar rupture in the “hydrogel” group requires 65% more force compared to the control group, while in the group of comparison this parameter made only 48%.

Preparation of nonleaching antimicrobial polypropylene wax and its application in polypropylene

ABSTRACTAntimicrobial polypropylene (PP) has been widely used. Its highly effective antimicrobial activities and nonleaching characteristics remain concerns. In this study, polypropylene wax (PPW) grafted with maleic anhydride was first prepared; this was followed by a melting reaction with polyhexamethylene guanidine hydrochloride (PHMG) to obtain antimicrobial PPW [polypropylene wax grafted with polyhexamethylene guanidine hydrochloride (PPW‐g‐PHMG)]. PPW‐g‐PHMG was then melt‐blended with PP to prepare antimicrobial PP. Fourier transform infrared spectra confirmed that PHMG was covalently bonded on the PPW chains, and transmission electron microscopy images showed a uniform distribution of PHMG in the PPW matrix. The resulting antimicrobial PP exhibited excellent antimicrobial activity against Escherichia coli. The ring‐diffusion test further disclosed its nonleaching characteristics. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44190.

Antifungal activity of the cationic antimicrobial polymer-polyhexamethylene guanidine hydrochloride and its mode of action

The antifungal activity of polyhexamethylene guanidine hydrochloride (PHMGH) was studied against various pathogenic fungi. PHMGH had more potent antifungal activity than amphotericin B, which is a commonly used antifungal drug, and also showed no hemolytic and lactate dehydrogenase release activities in the range of 1.25–40.0 μg mL−1. PHMGH is a cationic polymer containing an amino group and a polymeric guanidine group. Based on its characteristics such as the cationic charge and hydrophobicity, the antifungal mechanism of PHMGH was investigated using Candida albicans, as a model organism. Flow cytometric contour-plot analysis and microscopy showed changes in the size and granularity of the cells after treatment with PHMGH. A membrane study using 1,6-diphenyl-1,3,5-hexatriene labelling indicated a great loss of phospholipid area in the plasma membrane following PHMGH treatment. To investigate the extent of the damage, fluorescein isothiocyanate-labelled dextran leakage from large unilamellar vesicles was observed, indicating that PHMGH acts on the fungal membranes by inducing pore formation, with the majority of pore size being between 2.3 and 3.3 nm. This mechanism was confirmed with ion transition assays using 3,3′-dipropylthiacarbocyanine iodide and an ion-selective electrode meter, which indicated that membrane depolarization involving K+ leakage was induced. Taken together, these results show that PHMGH exerts its fungicidal effect by forming pores in the cell membrane.

Poly(hexamethylene guanidine)-poly(ethylene glycol) solid blend for water microbial deactivation

Polyhexamethylene guanidine hydrochloride (PHMG) is a cationic polymeric biocide used in the treatment of contaminated drinking water. This article describes a PHMG controlled release system made from melt blend of PHMG and solid PEG rods. The polymeric blend system gradually dissolves upon contact with running water and release effective and safe doses of PHMG to the passing water. The PEG-PHMG rod units were installed in a water purifier system, and microbial inactivation efficiency was tested according to the WQA certification program against P231/EPA for 250 L, using 25 L of passing water per day with a flow rate of 8–10 min per liter. The released PHMG was analyzed by Raman spectroscopy, and the antimicrobial activity was determined against Escherichia coli and the virus surrogate, MS2. A constant release of 0.35–0.5 ppm PHMG along 250 L of passing water was achieved. Inactivation results exceeded the minimal requirement for bacterial removal of 4–5 log reduction throughout the entire 250L. The rod height correlated with amount of water eroding the rod from bottom surface. Thus, these PEG/PHMG rod unit systems can be used in water purification to provide microbial free drinking water and serve as an indicator for quantity of water passing through the filter.

Influence of the Scaling Inhibitor on the Phase Composition, Morphology, and Sedimentation Properties of CaCO3 Deposits

We study the influence of OK-2 scaling inhibitor based on polyhexamethyleneguanidine hydrochloride on the morphology and phase composition of calcium carbonate. It is established that the presence of inhibitor in the solution leads to an increase in the sizes of crystals in the deposit and the predominance of needle structures in it. The aragonite and calcite phases are in excess in the deposits of calcium carbonate and the presence of inhibitor in the solution increases the amount of calcite by 21%. The revealed effects are caused by the adsorption of the inhibitor on carbonate deposits, which can be described by the Langmuir isotherm. The adsorption of the inhibitor leads to the recharging of the CaCO3 surface and to the increase in the size of particles of the dispersed phase, which promotes its faster precipitation.

Guanicid and PHMG Toxicity Tests on Aquatic Organisms

The emergence and development of new algicidal products is caused by the ever increasing popularity of garden ponds as well as the use of these products in the fisheries sector, especially for disposal of cyanobacteria and algae. Most frequent means of combating cyanobacteria and algae are applications of algicidal substances. Newly developed algaecides include Guanicid and polyhexamethylene guanidine hydrochloride (PHMG). The aim of the study was to identify toxic effects of Guanicid and PHMG on zebrafish (Danio rerio) and green algae (Desmodesmus communis). We determined the acute toxicity in fish according to ČSN EN ISO 7346-1, and conducted the freshwater algae growth inhibition test according to ČSN ISO 8692 methodology. For inhibition tests with green algae we chose Guanicid and PHMG concentrations of 0.001, 0.005, and 0.010 ml/L. For fish short-term acute toxicity tests we chose Guanicid concentrations of 0.010, 0.050, 0.150, 0.200, 0.250, and 0.300 ml/L and PHMG concentrations of 0.010, 0.025, 0.050, 0.075, 0.100, and 0.125 ml/L. In case of zebrafish (Danio rerio), the LC50 value for Guanicid is 0.086 ml/L, while the LC50 value for PHMG is 0.043 ml/L. Effects of Guanicid on inhibition of green algae (Desmodesmus communis) appear highly significant (p < 0.010) at a concentration of 0.010 ml/L. For PHMG, these effects are highly significant (p < 0.001) at concentrations of 0.005 and 0.010 ml/L in 48 hours.

Влияние композиций метацида на рост зерновых культур

Сomplexes and associates of surfactants with polymers and polyelectrolytes represent a new group of the effective surfactants. Obtained polycomplexes in the difference from individual components show specific properties and they can be considered as a new macromolecular surfactants. The paper considers the influence of bactericidal polyelectrolyte polyhexamethyleneguanidine hydrochloride (metacide), polyethylene glycol and anionic surface active sodium dodecyl sulfate and their compositions on the germination, growth and stress tolerance of crops. The use of compositions is beneficial to the growth of crops, improvement of their ability to the stress tolerance. In the result of study, the sample processed with a metacide - polyethylene glycol solution showed high rates. Therefore, in the presence of metacide, polyethylene glycol and their complexes the crops are resistant to environmental factors.

Bio-Wax Latex-Modified Paper as Antimicrobial and Water-Vapor-Resistant Packaging Material

Beeswax and carnauba wax latex particles grafted with antimicrobial agents polyhexamethylene guanidine hydrochloride and polyhexanide were prepared by coupling reaction using N-(3-dimethylaminopropyl)-N’-ethylcarbodiimide hydrochloride as a coupling reagent. As a bifunctional agent for the surface treatment of paper the modified bio-wax latex improved the property of water-vapor resistance and antimicrobial activities of paper significantly after coating. Compared with the control sample the water vapor transmission rate (WVTR) of the paper with coating weight of 12 g/m2 was reduced significantly from 2788.8 g/m2/d to 222.0 g/m2/d (BW-Gly-PHGH) thus demonstrating excellent water vapor barrier performance. The shaking flask method was utilized to investigate the antimicrobial activity against E. coli. The results showed that antimicrobial performance was improved substantially when the amount of added modified bio-wax particles was higher than 20 mg/g fiber. The bacterial inhibition ring test indicated that the antimicrobial mode of the modified bio-wax particles was likely based on the contact mode.

Non-leaching antimicrobial biodegradable PBAT films through a facile and novel approach

The antimicrobial thermoplastic starch (ATPS) containing guanidine-based polymers was obtained using a twin-screw extrusion with potato starch and polyhexamethylene guanidine hydrochloride (PHGH). Furthermore, the non-leaching antimicrobial biodegradable poly(butylene adipate-co-terephthalate) (PBAT) was prepared through reactive extrusion with PBAT and ATPS in the presence of the coupling agent, 2,2′-(1,3-phenylene)-bis (2-oxazoline) (PBO). Finally, the antimicrobial PBAT films were obtained by using a blown film extrusion system. The mechanical properties of the antimicrobial PBAT films varied with the contents of ATPS and thermoplastic starch (TPS). According to the test results of shaking flask method, the prepared antimicrobial PBAT films showed excellent antimicrobial activities (antimicrobial rate >99.99%) and rapid pathogen deactivation efficiency (antimicrobial rate >99.99% even within 15s of contact time). The water washing and ring diffusion tests demonstrated that the antimicrobial film was a non-leaching product. Inspiringly, the antimicrobial PBAT films with an excellent antimicrobial activity can be obtained even at a very low dosage of PHGH (1.0mg/g PBAT film).

Preparation and properties of polyacrylonitrile fibers with guanidine groups

The polyacrylonitrile (PAN) fibers grafted with guanidine groups were prepared by hydrolyzing with sodium hydroxide solution followed by reacting with polyhexamethylene guanidine hydrochloride (PHGC). The grafting degree could be controlled by changing the treatment time of hydrolyzed PAN fibers with PHGC. The chemical composition and morphology of the modified PAN fibers were characterized by Fourier transform infrared spectroscopy (FTIR), Elemental analysis (EA), X-ray photoelectric spectroscopy (XPS) and scanning electron microscope (SEM). The results showed that the guanidine groups were effectively grafted on the fibers. The water contact angle of the surface modified PAN fibers was reduced and moisture regain was improved significantly with the immobilization of PHGC on the fibers. Furthermore, the modified PAN fibers exhibited favorable acid dyeability at low temperature (50 °C) over a wide pH range and good mechanical properties. The simple and applicable synthesis process provides a new avenue for modification of PAN fibers with improved hydrophilicity and acid dyeability.

Developing of a novel antibacterial agent by functionalization of graphene oxide with guanidine polymer with enhanced antibacterial activity

New materials with excellent antibacterial activity attract numerous research interests. Herein, a facile synthetic method of polyethylene glycol (PEG) and polyhexamethylene guanidine hydrochloride (PHGC) dual-polymer-functionalized graphene oxide (GO) (GO-PEG-PHGC), a novel antibacterial material, was reported. The as-prepared products were characterized by scanning electron microscopy (SEM), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), X-ray pattern (XRD) and elemental analysis. The antibacterial effect on the bacterial strain was investigated by incubating both Gram-negative bacteria (Escherichia coli) and Gram-positive bacteria (Staphylococcus aureus). The results show that GO-PEG-PHGC has enhanced antibacterial activity when compared to GO, GO-PEG or GO-PHGC alone. The improved antibacterial activity was described to be related to a better dispersion of GO-PEG-PHGC in the presence of PEG. This better dispersion leads to a greater contact between the bacteria membrane and nanomaterials, therefore leading to greater cell damage. Not only Gram-negative bacteria but also Gram-positive bacteria are greatly inhibited by this antibacterial agent. With the powerful antibacterial activity as well as its low cost and facile preparation, the GO-PEG-PHGC as a novel antibacterial agent can find potential application in the areas of healthcare and environmental engineering.

Correlation between antibiotic and biocide resistance in mesophilic and psychrotrophic Pseudomonas spp. isolated from slaughterhouse surfaces throughout meat chain production

The aim of this study was to evaluate biocide susceptibility in mesophilic and psychrotrophic pseudomonads isolated from surfaces of a goat and lamb slaughterhouse, which was representative of the region. To determine biocide resistance in pseudomonads, we determined for the first time the epidemiological cut-off values (ECOFFs) of benzalkonium, cetrimide, chlorhexidine, hexachlorophene, P3 oxonia, polyhexamethylene guanidine hydrochloride (PHMG), topax 66 and triclosan being generally very similar in different Pseudomonas spp. with some exceptions. Thus, resistance of pseudomonads was mainly shown to triclosan, and in lesser extent to cetrimide and benzalkonium chloride depending on the species, however they were highly susceptible to industrial formulations of biocides. By means of statistical analysis, positive correlations between antibiotics, biocides and both antimicrobials in pseudomonads were detected suggesting a co- or cross resistance between different antimicrobials in goat and lamb slaughterhouse environment. Cross-resistance between biocides and antibiotics in pseudomonads were especially detected between PHMG or triclosan and different antibiotics depending on the biocide and the population type. Thus, the use of those biocides as disinfectant in slaughterhouse zones must be carefully evaluated because of the selection pressure effect of antimicrobials on the emergence of resistant bacteria which could be spread to the consumer. It is noteworthy that specific industrial formulations such as topax 66 and oxonia P3 showed few correlations with antibiotics (none or 1–2 antibiotics) which should be taken into consideration for disinfection practices in goat and lamb slaughterhouse.

Synthesis of Polyalkylguanidine Hydrochloride Copolymers and Their Antibacterial Activity Against Conditionally Pathogenic Microorganisms Bacillus Cereus and Escherichia Coli

Copolymers based on aliphatic diamines of various methylene chain lengths and guanidine hydrochloride were prepared by polycondensation in the melt. Antibacterial activity of water-soluble copolymers based on guanidine against conditionally pathogenic microorganisms Escherichia coli and Bacillus cereus was evaluated using diffusion in agar. Arelationship was found between the ratio of the number of hydrophobic methylene groups to the number of ionized guanidines and the antibacterial activity of the copolymers. Several samples showed high antimicrobial activity as compared with polyhexamethyleneguanidine hydrochloride (PHMGHC), which is widely used as a medical disinfectant.

Zeta potential study of biodegradable antimicrobial polymers

Abstract Biodegradable polymers have gained increasing interest in recent years, especially in food packaging industry. The biodegradation process is intrinsically related to adhesion of degradation-promoting bacteria on the surface of a biodegradable packaging. On the other hand, because of a direct contact with food, these materials should be resistant to colonisation by pathogenic bacteria. Thus, successful design of a biodegradable antimicrobial material critically depends on the interplay between the ability to control the strength of bacteria–polymer interactions. The aim of this work was to measure and analyse the effect of three positively charged antibacterial polyhexamethylene guanidine hydrochloride (PHMG) derivatives (sulfanilic acid salt, stearic acid salt, and polyethylene (PE) wax blend) on electrokinetic potential ( ζ ) of three biodegradable polymers: poly(hydroxybutyric acid) (PHB), polycaprolactone (PCL) and poly(lactic acid) (PLA). For this purpose, the streaming current vs pressure curves were recorded and analysed using the Helmholtz–Smoluchowski theory. The ζ vs pH dependency provides a simple and useful characterisation of an electrical double layer forming on the surface of biodegradable polymers in contact with an aqueous electrolyte. The undoped polymers displayed the ζ vs pH curves typical for electrically neutral polymers, with the isoelectric point, IEP = 3.5–4.0. The effect of PHMG on ζ vs pH curves depends on both the nature of the matrix polymer and the chemical form of PHMG. The stearate salt is shown to affect the curves to the smallest extent, while the most pronounced shifts towards higher pH were observed for PHMG in the form of PE wax (for PCL and PHB), or sulfanilic acid salt (for PLA). The surface of almost all PHMG-doped polymers used in this study (with exception of PLA doped with PHMG stearate) was more positive than the bare biodegradable polymers. From the point of view of electrostatic interactions, the addition of PHMG (especially in the form of PE wax, and especially for PHB) would thus probably enhance electrostatic polymer–bacteria interactions, possibly altering the antimicrobial activity of such polymers.

Antimicrobial polyethylene wax emulsion and its application on active paper‐based packaging material

ABSTRACTAntimicrobial polyethylene wax (PEW) emulsions, prepared by emulsifying polyethylene wax grafted with polyhexamethylene guanidine hydrochloride (PEW‐g‐PHGH), were used as wet‐end additives or coating materials for fabricating hydrophobic and anti‐mold hand‐sheets or paper. To obtain PEW‐g‐PHGH, maleic anhydride (MAH) was adopted as a bridging agent. The melt or solution grafting of MAH to PEW was performed to achieve the appropriate grafting degree and grafting efficiency. The resulting PEW‐g‐PHGH was emulsified using a homogenizer by means of surfactants, and the resulted emulsions were characterized in terms of particle size, zeta potential, charge density, minimal inhibitory concentration (MIC), and adsorption capacity. After that the hydrophobicity of emulsion treated hand‐sheets was determined by measuring water contact angle (WCA). The morphology of the hand‐sheets treated by the emulsion was revealed using scanning electron microscope (SEM) and atom force microscope (AFM). Finally, the antimicrobial properties of the emulsion treated hand‐sheets were investigated by anti‐mold tests against Aspergillus niger and Chaetomium globosum. Results indicated that the PEW‐g‐PHGH emulsions exhibited good stability, high fiber adsorption capacity, and antimicrobial activity. The WCAs of the treated hand‐sheets reached 82°–140° with 80%∼99.9% growth inhibition against fungi. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42214.

Soil burial biodegradation of antimicrobial biodegradable PBAT films

Recently, biodegradable polymers have been broadly used in various applications, including antimicrobial biodegradable composite materials. However, the biodegradability of such polymers in the presence of antimicrobial agents has barely been investigated. Moreover, whether the antimicrobial property of the material would be compromised or affected by the microorganisms in the soil is still unclear. In this work, the biodegradation behavior and antimicrobial property of the novel antimicrobial biodegradable poly(butylene adipate-co-terephthalate) (PBAT)/thermoplastic starch films before and after a three-month soil burial test have been investigated. The weight retention data showed that both PBAT and starch were still able to degrade even in the presence of the antimicrobial substance, polyhexamethylene guanidine hydrochloride (PHGH). However, the biodegradation rate was retarded. The antimicrobial films exhibited excellent growth inhibition against E. coli before biodegradation test. The film with the coupling agent 2,2′-(1,3-phenylene)-bis(2-oxazoline) (PBO) and less starch content presented a growth inhibition over 99% even after the three-month biodegradation test, due to a better PHGH retention. The semi-crystalline PBAT did not show any significant crystal structure change in the DSC analysis. Both SEM images and mechanical properties demonstrated the biodegradation of the films from the macro-scale.