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Membranes
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Functional Porous Membranes for Energy, Environmental and Biomedical Applications
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Functional Porous Membranes for Energy, Environmental and Biomedical Applications

A special issue of Membranes (ISSN 2077-0375). This special issue belongs to the section "Membrane Applications".

Deadline for manuscript submissions: closed (31 October 2022) | Viewed by 30249

Special Issue Editors

Dr. Nazely Diban

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Guest Editor
Department of Chemical and Biomolecular Engineering, ETSIIyT, University of Cantabria, Avda. Los Castros s/n, 39005 Santander, Spain
Interests: biopolymer membranes; mixed-matrix membranes; membrane synthesis; modeling; perfusion bioreactors; photocatalytic membranes; tissue engineering
Special Issues, Collections and Topics in MDPI journals
Dr. Enver Güler

E-Mail Website
Guest Editor
Department of Chemical Engineering, Atılım University, 06830 Ankara, Turkey
Interests: ion exchange membranes; polymer electrolytes for fuel cells; salinity gradient energy; membrane separation; water treatment
Dr. Izumi Kumakiri

E-Mail Website
Guest Editor
Department of Environmental Science and Engineering, Graduate School Science and Engineering, Yamaguchi University, Tokiwadai 2-16-1, Ube, Yamaguchi 755-8611, Japan
Interests: inorganic membranes; mixed-matrix membranes; membrane integrated processes; membrane reactors; nano-functional materials

Special Issue Information

Dear Colleagues,

The quest for preparing more efficient membranes is an emerging field with still many unsolved challenges ahead. Efficiency can be boosted by loading/blending or coating the membranes with active fillers/materials (inorganic nanomaterials (i.e. graphene, zeolites, ceramics, metals), polymers, ionic liquids, liquid crystals, etc.). The porous structure of the membrane also plays an important role in function and performance. The applications of the membranes cover a wide range of fields. The present Special Issue will focus on the applications of organic and inorganic membranes to get sustainable energy, environmental remediation, and biomedical solutions. This Special Issue will accept innovative research and review manuscripts that cover (but are not limited to) the following  topics:

  • New membrane synthesis methodologies,
  • New composite membrane materials,
  • Getting insights on mechanisms for membrane formation and performance of membrane function both experimentally and/or through modeling,
  • Experimental evaluation of porous membrane performance on membrane modules and membrane reactors
  • Scaling-up
  • Environmental and/or economic evaluation with simulation tools (i.e., Life Cycle Assessment) of membrane-based technologies

Dr. Nazely Diban
Dr. Enver Güler
Dr. Izumi Kumakiri
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Membranes is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • Advanced active materials
  • Composites
  • Ionic liquids
  • Nanomaterials
  • Membrane reactors
  • Membrane synthesis
  • Biomedical applications
  • Energy applications
  • Photocatalysis
  • Water treatment

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Published Papers (11 papers)

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Research

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13 pages, 2499 KiB  
Article
Performance of TiO2-Based Tubular Membranes in the Photocatalytic Degradation of Organic Compounds
by Carmen Barquín, Aranza Vital-Grappin, Izumi Kumakiri, Nazely Diban, Maria J. Rivero, Ane Urtiaga and Inmaculada Ortiz
Membranes 2023, 13(4), 448; https://doi.org/10.3390/membranes13040448 - 20 Apr 2023
Cited by 2 | Viewed by 2441
Abstract
This work presents the photocatalytic degradation of organic pollutants in water with TiO2 and TiO2/Ag membranes prepared by immobilising photocatalysts on ceramic porous tubular supports. The permeation capacity of TiO2 and TiO2/Ag membranes was checked before the [...] Read more.
This work presents the photocatalytic degradation of organic pollutants in water with TiO2 and TiO2/Ag membranes prepared by immobilising photocatalysts on ceramic porous tubular supports. The permeation capacity of TiO2 and TiO2/Ag membranes was checked before the photocatalytic application, showing high water fluxes (≈758 and 690 L m−2 h−1 bar−1, respectively) and <2% rejection against the model pollutants sodium dodecylbenzene sulfonate (DBS) and dichloroacetic acid (DCA). When the membranes were submerged in the aqueous solutions and irradiated with UV-A LEDs, the photocatalytic performance factors for the degradation of DCA were similar to those obtained with suspended TiO2 particles (1.1-fold and 1.2-fold increase, respectively). However, when the aqueous solution permeated through the pores of the photocatalytic membrane, the performance factors and kinetics were two-fold higher than for the submerged membranes, mostly due to the enhanced contact between the pollutants and the membranes photocatalytic sites where reactive species were generated. These results confirm the advantages of working in a flow-through mode with submerged photocatalytic membranes for the treatment of water polluted with persistent organic molecules, thanks to the reduction in the mass transfer limitations. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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21 pages, 5018 KiB  
Article
High-Frequency Pulsatile Parameterization Study for the Titania Ceramic Membrane Fouling Mitigation in Oily Wastewater Systems Using the Box–Behnken Response Surface Methodology
by Mohamed Echakouri, Amr Henni and Amgad Salama
Membranes 2022, 12(12), 1198; https://doi.org/10.3390/membranes12121198 - 28 Nov 2022
Cited by 7 | Viewed by 1806
Abstract
In this comprehensive study, a seven-channel ultrafiltration (UF) titania membrane was used to investigate the impact of the pulsatile cleaning process on the crossflow filtration system. Seventeen experimental runs were performed for different operating conditions with a transmembrane pressure (TMP) varying from 0.5 [...] Read more.
In this comprehensive study, a seven-channel ultrafiltration (UF) titania membrane was used to investigate the impact of the pulsatile cleaning process on the crossflow filtration system. Seventeen experimental runs were performed for different operating conditions with a transmembrane pressure (TMP) varying from 0.5 to 1.5 bar, a crossflow velocity (CFV) ranging from 0.5 to 1 m/s, and pulsatile parameters within an interval varying from 60 to 120 s with a duration of 0.8 s, and collecting membrane permeate flux and volume data. The optimized operating conditions revealed that a TMP of 1.5 bar, a CFV of 0.71 m/s, and a pulsatile cycle of 85 s were the best operating conditions to reach the highest steady permeability flux and volume of 302 LMH and 8.11 L, respectively. The UF ceramic membrane under the optimized inputs allowed for an oil-rejection ability of 99%. The Box–Behnken design (BBD) model was used to analyze the effect of crossflow operating conditions on the permeate flux and volume. The analysis of variance (ANOVA) indicated that the quadratic regression models were highly significant. At a 95% confidence interval, the optimum TMP significantly enhanced the flux and permeate volume simultaneously. The results also demonstrated a positive interaction between the TMP and the pulsatile process, enhancing the permeate flux with a slight impact on the permeate volume. At the same time, the interaction between the CFV and pulsatile flow improved the permeability and increased the permeate volume. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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33 pages, 13420 KiB  
Article
Composite GO/Ceramic Membranes Prepared via Chemical Attachment: Characterisation and Gas Permeance Properties
by Evdokia Galata, Charitomeni M. Veziri, George V. Theodorakopoulos, George Em. Romanos and Evangelia A. Pavlatou
Membranes 2022, 12(12), 1181; https://doi.org/10.3390/membranes12121181 - 24 Nov 2022
Cited by 7 | Viewed by 2928
Abstract
Graphene oxide (GO) oligo-layered laminates were self-assembled on porous ceramic substrates via their simple dip-coating into aqueous GO dispersions. To augment the stability of the developed composite GO/ceramic membranes and control the morphology and stacking quality of the formed laminate, short-((3-glycidoxypropyl)trimethoxy silane-GLYMO, (3-aminopropyl)triethoxy [...] Read more.
Graphene oxide (GO) oligo-layered laminates were self-assembled on porous ceramic substrates via their simple dip-coating into aqueous GO dispersions. To augment the stability of the developed composite GO/ceramic membranes and control the morphology and stacking quality of the formed laminate, short-((3-glycidoxypropyl)trimethoxy silane-GLYMO, (3-aminopropyl)triethoxy silane-APTES), and long-chain (polydopamine-PDA) molecules were involved and examined as interfacial linkers. A comparative study was performed regarding the linker’s capacity to enhance the interfacial adhesion between the ceramic surface and the GO deposit and affect the orientation and assemblage characteristics of the adjacent GO nanosheets that composed the formed oligo-layered laminates. Subsequently, by post-filtrating a GO/H2O suspension through the oligo-layered laminate membranes, the respective multi-layered ones have been developed, whereas ethylenediamine (EDA) was used in the suspension as an efficient molecular linker that strongly bonds and interlocks the GO nanosheets. The definition of the best linker and approach was conducted on macroporous α-alumina disks, due to the use of inexpensive raw materials and the ability to fabricate them in the lab with high reproducibility. To validate the concept at a larger scale, while investigating the effect of the porous substrate as regards its micrometer-scale roughness and surface chemistry, specific chemical modifications that yielded membranes with the best gas permeability/selectivity performance were replicated on a commercial single-channel monolith with a ZrO2 microfiltration layer. XRD, Raman, ATR, FESEM, and XPS analyses were conducted to study the structural, physicochemical, surface, and morphological properties of the GO/ceramic composite membranes, whereas permeance results of several gases at various temperatures and trans-membrane pressures were interpreted to shed light on the pore structural features. Concerning the short-chain linkers, the obtained results ascertain that GLYMO causes denser and more uniform assembly of GO nanosheets within the oligo-layered laminate. PDA had the same beneficial effect, as it is a macromolecule. Overall, this study shows that the development of gas-separating membranes, by just dipping the linker-modified substrate into the GO suspension, is not straightforward. The application of post-filtration contributed significantly to this target and the quality of the superficially deposited, thick GO laminate depended on this of the chemically attached oligo-layered one. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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19 pages, 3377 KiB  
Article
Amphiphilic Chitosan Porous Membranes as Potential Therapeutic Systems with Analgesic Effect for Burn Care
by Andra-Cristina Enache, Petrisor Samoila, Corneliu Cojocaru, Adrian Bele, Andra-Cristina Bostanaru, Mihai Mares and Valeria Harabagiu
Membranes 2022, 12(10), 973; https://doi.org/10.3390/membranes12100973 - 5 Oct 2022
Cited by 3 | Viewed by 2127
Abstract
Eliminating or at least lessening the pain is a crucial aspect of burns management, as pain can negatively affect mental health and quality of life, and it can also induce a delay on wound healing. In this context, new amphiphilic chitosan 3D porous [...] Read more.
Eliminating or at least lessening the pain is a crucial aspect of burns management, as pain can negatively affect mental health and quality of life, and it can also induce a delay on wound healing. In this context, new amphiphilic chitosan 3D porous membranes were developed and investigated as burns therapeutic systems with analgesic effect for delivery of lidocaine as local anesthetic. The highly porous morphology of the membranes and the structural modifications were evidenced by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) analysis and infrared spectroscopy (FTIR). Improved compression mechanical properties, long-term hydrolytic degradation (28 days) evaluation and high swelling capacities (ranging from 8 to 22.6 g/g) indicate an increased capacity of the prepared membranes to absorb physiological fluids (burns exudate). Lidocaine in vitro release efficiency was favored by the decreased content of cross-linking agent (reaching maximum value of 95.24%) and the kinetic data modeling, indicating that lidocaine release occurs by quasi-Fickian diffusion. In addition to the in vitro evaluation of analgesic effect, lidocaine-loaded chitosan membranes were successfully investigated and proved antibacterial activity against most common pathogens in burns infections: Staphylococcus aureus and Methicillin-resistant Staphylococcus aureus. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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12 pages, 2788 KiB  
Article
Computational Studies on Holey TMC6 (TM = Mo and W) Membranes for H2 Purification
by Juan Xie, Cai Ning, Qinqin Liu, Zhongti Sun, Juan Yang and Huilong Dong
Membranes 2022, 12(7), 709; https://doi.org/10.3390/membranes12070709 - 14 Jul 2022
Cited by 1 | Viewed by 1588
Abstract
The purification of hydrogen (H2) has been a vital step in H2 production processes such as steam–methane reforming. By first-principle calculations, we revealed the potential applications of holey TMC6 (TM = Mo and W) membranes in H2 purification. [...] Read more.
The purification of hydrogen (H2) has been a vital step in H2 production processes such as steam–methane reforming. By first-principle calculations, we revealed the potential applications of holey TMC6 (TM = Mo and W) membranes in H2 purification. The adsorption and diffusion behaviors of five gas molecules (including H2, N2, CO, CO2, and CH4) were compared on TMC6 membranes with different phases. Though the studied gas molecules show weak physisorption on the TMC6 membranes, the smaller pore size makes the gas molecules much more difficult to permeate into h-TMC6 rather than into s-TMC6. With suitable pore sizes, the s-TMC6 structures not only show an extremely low diffusion barrier (around 0.1 eV) and acceptable permeance capability for the H2 but also exhibit considerably high selectivity for both H2/CH4 and H2/CO2 (>1015), especially under relatively low temperature (150–250 K). Moreover, classical molecular dynamics simulations on the permeation process of a H2, CO2, and CH4 mixture also validated that s-TMC6 could effectively separate H2 from the gas mixture. Hence, the s-MoC6 and s-WC6 are predicted to be qualified H2 purification membranes, especially below room temperature. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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17 pages, 4815 KiB  
Article
Immobilization of poly(vinyl pyrrolidone) in Polysulfone Membranes by Radically-Initiated Crosslinking Using Potassium Persulfate
by Danae Gonzalez Ortiz, Morgan Nouxet, William Maréchal, Olivier Lorain, André Deratani and Céline Pochat-Bohatier
Membranes 2022, 12(7), 664; https://doi.org/10.3390/membranes12070664 - 28 Jun 2022
Cited by 5 | Viewed by 2264
Abstract
Polysulfone (PSU) membranes with poly(vinyl pyrrolidone) (PVP) as a pore-forming and hydrophilic additive were prepared using the non-solvent-induced phase separation (NIPS) technique. PVP immobilization by radical-initiated crosslinking using potassium persulfate (KPS) was studied in view of obtaining membranes with high and long-lasting surface [...] Read more.
Polysulfone (PSU) membranes with poly(vinyl pyrrolidone) (PVP) as a pore-forming and hydrophilic additive were prepared using the non-solvent-induced phase separation (NIPS) technique. PVP immobilization by radical-initiated crosslinking using potassium persulfate (KPS) was studied in view of obtaining membranes with high and long-lasting surface hydrophilicity. A method based on the ATR-FTIR technique was developed to discriminate crosslinked PVP from unreacted PVP in the membrane. The crosslinking progress was investigated as a function of temperature, KPS concentration, and reaction time. The results showed that temperature was the main factor influencing the crosslinking reaction since radical formation is temperature-dependent. Increasing the concentration of KPS and the reaction time led to an increase in the crosslinking rate. The effect of the degree of PVP crosslinking on the structure and properties of the prepared membranes was examined by studying mechanical properties, morphology by SEM, surface hydrophilicity by contact angle measurements, and water permeability. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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17 pages, 28383 KiB  
Article
Wicking in Porous Polymeric Membranes: Determination of an Effective Capillary Radius to Predict the Flow Behavior in Lateral Flow Assays
by Patrick Altschuh, Willfried Kunz, Marcel Bremerich, Andreas Reiter, Michael Selzer and Britta Nestler
Membranes 2022, 12(7), 638; https://doi.org/10.3390/membranes12070638 - 21 Jun 2022
Cited by 8 | Viewed by 3084
Abstract
The working principle of lateral flow assays, such as the widely used COVID-19 rapid tests, is based on the capillary-driven liquid transport of a sample fluid to a test line using porous polymeric membranes as the conductive medium. In order to predict this [...] Read more.
The working principle of lateral flow assays, such as the widely used COVID-19 rapid tests, is based on the capillary-driven liquid transport of a sample fluid to a test line using porous polymeric membranes as the conductive medium. In order to predict this wicking process by simplified analytical models, it is essential to determine an effective capillary radius for the highly porous and open-pored membranes. In this work, a parametric study is performed with selected simplified structures, representing the complex microstructure of the membrane. For this, a phase-field approach with a special wetting boundary condition to describe the meniscus formation and the corresponding mean surface curvature for each structure setup is used. As a main result, an analytical correlation between geometric structure parameters and an effective capillary radius, based on a correction factor, are obtained. The resulting correlation is verified by applying image analysis methods on reconstructed computer tomography scans of two different porous polymeric membranes and thus determining the geometric structure parameters. Subsequently, a macroscale flow model that includes the correlated effective pore size and geometrical capillary radius is applied, and the results are compared with wicking experiments. Based on the derived correction function, it is shown that the analytical prediction of the wicking process in highly porous polymeric membranes is possible without the fitting of experimental wicking data. Furthermore, it can be seen that the estimated effective pore radius of the two membranes is 8 to 10 times higher than their geometric mean pore radii. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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16 pages, 3891 KiB  
Article
A Methyl-Modified Silica Layer Supported on Porous Ceramic Membranes for the Enhanced Separation of Methyl Tert-Butyl Ether from Aqueous Solution
by Ligang Xu, Yali Wang, Qunyan Li, Suping Cui, Mingxue Tang, Zuoren Nie and Qi Wei
Membranes 2022, 12(5), 452; https://doi.org/10.3390/membranes12050452 - 22 Apr 2022
Cited by 4 | Viewed by 2473
Abstract
As a kind of volatile organic compound (VOC), methyl tert-butyl ether (MTBE) is hazardous to human health and destructive to the environment if not handled properly. MTBE should be removed before the release of wastewater. The present work supported the methyl-modified silica layer [...] Read more.
As a kind of volatile organic compound (VOC), methyl tert-butyl ether (MTBE) is hazardous to human health and destructive to the environment if not handled properly. MTBE should be removed before the release of wastewater. The present work supported the methyl-modified silica layer (MSL) on porous α-Al2O3 ceramic membranes with methyltrimethoxysilane (MTMS) as a precursor and pre-synthesized mesoporous silica microspheres as dopants by the sol-gel reaction and dip-coating method. MTMS is an environmentally friendly agent compared to fluorinated alkylsilane. The MSL-supported Al2O3 ceramic membranes were used for MTBE/water separation by pervaporation. The NMR spectra revealed that MTMS evolves gradually from an oligomer to a highly cross-linked methyl-modified silica species. Methyl-modified silica species and pre-synthesized mesoporous silica microspheres combine into hydrophobic mesoporous MSL. MSL makes the α-Al2O3 ceramic membranes transfer from amphiphilic to hydrophobic and oleophilic. The MSL-supported α-Al2O3 ceramic membranes (MSL-10) exhibit an MTBE/water separation factor of 27.1 and a total flux of 0.448 kg m−2 h−1, which are considerably higher than those of previously reported membranes that are modified by other alkylsilanes via the post-grafting method. The mesopores within the MSL provide a pathway for the transport of MTBE molecules across the membranes. The presence of methyl groups on the external and inner surface is responsible for the favorable separation performance and the outstanding long-term stability of the MSL-supported porous α-Al2O3 ceramic membranes. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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14 pages, 4239 KiB  
Article
Comparison of Physicochemical Properties of Two Types of Polyepichlorohydrin-Based Anion Exchange Membranes for Reverse Electrodialysis
by Ezgi Karakoç and Enver Güler
Membranes 2022, 12(3), 257; https://doi.org/10.3390/membranes12030257 - 24 Feb 2022
Cited by 11 | Viewed by 2533
Abstract
The development of the most effective, suitable and economic ion-exchange membranes is crucial for reverse electrodialysis (RED)—the most widely studied process to harvest salinity gradient energy from mixing seawater and river water. RED utilizes two types of membranes as core elements, namely cation [...] Read more.
The development of the most effective, suitable and economic ion-exchange membranes is crucial for reverse electrodialysis (RED)—the most widely studied process to harvest salinity gradient energy from mixing seawater and river water. RED utilizes two types of membranes as core elements, namely cation exchange membranes (CEM) and anion exchange membranes (AEM). Since the preparation of AEMs is more complex compared to CEMs, the design and development of anion exchange membranes have been the focus in this study. Homogeneous AEMs based on two types of polyepichlorohydrin (PECH) with different chlorine amounts (PECH-H, 37 wt% and PECH-C, 25 wt%) were synthesized, and first-time benchmarking of the membrane properties was conducted. In addition to physicochemical membrane properties, some instrumental analyses such as SEM, FTIR and DSC were investigated to characterize these anion-exchange membranes. Based on the results, although the PECH-H-type membrane had enhanced ion-exchange properties, PECH-C-based anion-exchange membranes exhibited a higher power density of 0.316 W/m2 in a lab-scale RED system. Evidently, there is room for the development of new types of PECH-C-based AEMs with great potential for energy generation in the RED process. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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19 pages, 2946 KiB  
Article
Intensification of Dry Reforming of Methane on Membrane Catalyst: Confirmation and Development of the Hypothesis
by Natalia Gavrilova, Sergey Gubin, Maria Myachina, Valentin Sapunov and Valery Skudin
Membranes 2022, 12(2), 136; https://doi.org/10.3390/membranes12020136 - 23 Jan 2022
Cited by 3 | Viewed by 2756
Abstract
This article presents an analysis of kinetic studies of dry methane reforming (DRM) in a reactor with a membrane catalyst (RMC) in the modes of a contactor with “diffusion” and “forced” mass transfer. Comparison of the specific rate constants of the methane dissociation [...] Read more.
This article presents an analysis of kinetic studies of dry methane reforming (DRM) in a reactor with a membrane catalyst (RMC) in the modes of a contactor with “diffusion” and “forced” mass transfer. Comparison of the specific rate constants of the methane dissociation reaction in membrane and traditional reactors confirmed the phenomenon of intensification of dry methane reforming in a membrane catalyst (MC). It has been experimentally established that during DRM, a temperature gradient arises in the channels of the pore structure of the membrane catalyst, characterized by a decrease in temperature towards the inner volume of the MC, and initiates the phenomenon of thermal slip. The features of this phenomenon are highlighted and must be considered in the analysis of kinetic data. The main provisions of the hypothesis explaining the effect of intensification by the occurrence of thermal slip in the channels of the pore structure of the MC are formulated. The proposed hypothesis, based on thermal slip, explains the difference in rate constants of traditional and membrane catalysts, and substantiates the phenomenological scheme of DRM stages in a reactor with a membrane catalyst. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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Review

Jump to: Research

50 pages, 2217 KiB  
Review
Polyhexanide-Releasing Membranes for Antimicrobial Wound Dressings: A Critical Review
by António Jorge Guiomar and Ana M. Urbano
Membranes 2022, 12(12), 1281; https://doi.org/10.3390/membranes12121281 - 18 Dec 2022
Cited by 10 | Viewed by 4744
Abstract
The prevalence of chronic, non-healing skin wounds in the general population, most notably diabetic foot ulcers, venous leg ulcers and pressure ulcers, is approximately 2% and is expected to increase, driven mostly by the aging population and the steady rise in obesity and [...] Read more.
The prevalence of chronic, non-healing skin wounds in the general population, most notably diabetic foot ulcers, venous leg ulcers and pressure ulcers, is approximately 2% and is expected to increase, driven mostly by the aging population and the steady rise in obesity and diabetes. Non-healing wounds often become infected, increasing the risk of life-threatening complications, which poses a significant socioeconomic burden. Aiming at the improved management of infected wounds, a variety of wound dressings that incorporate antimicrobials (AMDs), namely polyhexanide (poly(hexamethylene biguanide); PHMB), have been introduced in the wound-care market. However, many wound-care professionals agree that none of these wound dressings show comprehensive or optimal antimicrobial activity. This manuscript summarizes and discusses studies on PHMB-releasing membranes (PRMs) for wound dressings, detailing their preparation, physical properties that are relevant to the context of AMDs, drug loading and release, antibacterial activity, biocompatibility, wound-healing capacity, and clinical trials conducted. Some of these PRMs were able to improve wound healing in in vivo models, with no associated cytotoxicity, but significant differences in study design make it difficult to compare overall efficacies. It is hoped that this review, which includes, whenever available, international standards for testing AMDs, will provide a framework for future studies. Full article
(This article belongs to the Special Issue Functional Porous Membranes for Energy, Environmental and Biomedical Applications)
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