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Polymeric Materials from Chemistry, Functional and Biological Characterization to Applications

A special issue of International Journal of Molecular Sciences (ISSN 1422-0067). This special issue belongs to the section "Materials Science".

Deadline for manuscript submissions: closed (31 March 2023) | Viewed by 36556

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Guest Editor
Department of Chemistry in Pharmaceutical Sciences, Faculty of Pharmacy, Complutense University of Madrid (UCM), 28040 Madrid, Spain
Interests: polymer chemistry; natural polymers; green processes; metallic nanoparticles; drug delivery; antimicrobial; polimeric matrix; biomaterials; composites
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Guest Editor
Departamento de Química en Ciencias Farmacéuticas, Facultad de Farmacia, Universidad Complutense de Madrid, 28040 Madrid, Spain
Interests: biopolymers; chitosan derivatives; physico-chemical and functional characterization; green processes; polymer networks; biomaterials; drug delivery; pharmaceutical formulation
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Either synthetic or natural polymeric materials play a fundamental role in a myriad of applications. In biomedicine, they are used as drug delivery systems, biosensors or medical devices; in agriculture as protective films or delivery matrix; in the food industry as food packaging. In environmental applications, they are used in bioremediation or as purifying water membranes.

This Special Issue aims to cover all the aspects related to recent innovations in polymer materials field from their chemistry to their functional and biological characterization. In particular, the biological characterization includes aspects related to toxicity from a wide perspective. Not only the toxicity in biomedical applications but also environmental toxicity with the aim of boost an eco-friendlier vision of polymeric materials. So, discussion of the manufacturing of the advanced polymeric materials and their application in different fields are also welcome.

It is our pleasure to invite you to submit a manuscript for this Special Issue. Full papers, communications, and reviews are all welcome.

Dr. Inmaculada Aranaz Corral
Dr. Florentina Niuris Acosta Contreras
Guest Editors

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Keywords

  • Antimicrobial
  • Polymer chemistry
  • Chitosan
  • Drug delivery
  • Crop protection
  • Films and coatings
  • Toxicity
  • Eco-friendly

Published Papers (14 papers)

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Research

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19 pages, 17061 KiB  
Article
Wet-Spun Chitosan–Sodium Caseinate Fibers for Biomedicine: From Spinning Process to Physical Properties
by Hazel Peniche, Ivy Ann Razonado, Pierre Alcouffe, Guillaume Sudre, Carlos Peniche, Anayancy Osorio-Madrazo and Laurent David
Int. J. Mol. Sci. 2024, 25(3), 1768; https://doi.org/10.3390/ijms25031768 - 01 Feb 2024
Viewed by 816
Abstract
We designed and characterized chitosan–caseinate fibers processed through wet spinning for biomedical applications such as drug delivery from knitted medical devices. Sodium caseinate was either incorporated directly into the chitosan dope or allowed to diffuse into the chitosan hydrogel from a coagulation bath [...] Read more.
We designed and characterized chitosan–caseinate fibers processed through wet spinning for biomedical applications such as drug delivery from knitted medical devices. Sodium caseinate was either incorporated directly into the chitosan dope or allowed to diffuse into the chitosan hydrogel from a coagulation bath containing sodium caseinate and sodium hydroxide (NaOH). The latter route, where caseinate was incorporated in the neutralization bath, produced fibers with better mechanical properties for textile applications than those formed by the chitosan–caseinate mixed collodion route. The latter processing method consists of enriching a pre-formed chitosan hydrogel with caseinate, preserving the structure of the semicrystalline hydrogel without drastically affecting interactions involved in the chitosan self-assembly. Thus, dried fibers, after coagulation in a NaOH/sodium caseinate aqueous bath, exhibited preserved ultimate mechanical properties. The crystallinity ratio of chitosan was not significantly impacted by the presence of caseinate. However, when caseinate was incorporated into the chitosan dope, chitosan–caseinate fibers exhibited lower ultimate mechanical properties, possibly due to a lower entanglement density in the amorphous phase of the chitosan matrix. A standpoint is to optimize the chitosan–caseinate composition ratio and processing route to find a good compromise between the preservation of fiber mechanical properties and appropriate fiber composition for potential application in drug release. Full article
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20 pages, 15155 KiB  
Article
Contribution of the Surface Treatment of Nanofibrillated Cellulose on the Properties of Bio-Based Epoxy Nanocomposites Intended for Flexible Electronics
by Adriana Nicoleta Frone, Cătălina Diana Uşurelu, Gabriela Mădălina Oprică, Denis Mihaela Panaitescu, Augusta Raluca Gabor, Cristian-Andi Nicolae, Florin Ciuprina, Celina Maria Damian and Florentina Monica Raduly
Int. J. Mol. Sci. 2023, 24(7), 6544; https://doi.org/10.3390/ijms24076544 - 31 Mar 2023
Viewed by 1345
Abstract
The growing interest in materials derived from biomass has generated a multitude of solutions for the development of new sustainable materials with low environmental impact. We report here, for the first time, a strategy to obtain bio-based nanocomposites from epoxidized linseed oil (ELO), [...] Read more.
The growing interest in materials derived from biomass has generated a multitude of solutions for the development of new sustainable materials with low environmental impact. We report here, for the first time, a strategy to obtain bio-based nanocomposites from epoxidized linseed oil (ELO), itaconic acid (IA), and surface-treated nanofibrillated cellulose (NC). The effect of nanofibrillated cellulose functionalized with silane (NC/S) and then grafted with methacrylic acid (NC/SM) on the properties of the resulted bio-based epoxy systems was thoroughly investigated. The differential scanning calorimetry (DSC) results showed that the addition of NCs did not influence the curing process and had a slight impact on the maximum peak temperature. Moreover, the NCs improved the onset degradation temperature of the epoxy-based nanocomposites by more than 30 °C, regardless of their treatment. The most important effect on the mechanical properties of bio-based epoxy nanocomposites, i.e., an increase in the storage modulus by more than 60% at room temperature was observed in the case of NC/SM addition. Therefore, NC’s treatment with silane and methacrylic acid improved the epoxy–nanofiber interface and led to a very good dispersion of the NC/SM in the epoxy network, as observed by the SEM investigation. The dielectric results proved the suitability of the obtained bio-based epoxy/NCs materials as substitutes for petroleum-based thermosets in the fabrication of flexible electronic devices. Full article
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16 pages, 3217 KiB  
Communication
Polyacrylamide Hydrogel Containing Calendula Extract as a Wound Healing Bandage: In Vivo Test
by Lindalva Maria de Meneses Costa Ferreira, Elanne de Sousa Bandeira, Maurício Ferreira Gomes, Desireé Gyles Lynch, Gilmara Nazareth Tavares Bastos, José Otávio Carréra Silva-Júnior and Roseane Maria Ribeiro-Costa
Int. J. Mol. Sci. 2023, 24(4), 3806; https://doi.org/10.3390/ijms24043806 - 14 Feb 2023
Cited by 5 | Viewed by 2126
Abstract
Hydrogel is a biomaterial widely used in several areas of industry due to its great biocompatibility and adaptability to biological tissues. In Brazil, the Calendula plant is approved by the Ministry of Health as a medicinal herb. It was chosen to be incorporated [...] Read more.
Hydrogel is a biomaterial widely used in several areas of industry due to its great biocompatibility and adaptability to biological tissues. In Brazil, the Calendula plant is approved by the Ministry of Health as a medicinal herb. It was chosen to be incorporated in the hydrogel formulation because of its anti-inflammatory, antiseptic and healing effects. This study synthesized polyacrylamide hydrogel containing calendula extract and evaluated its efficiency as a bandage for wound healing. The hydrogels were prepared using free radical polymerization and characterized by Scanning Electron Microscopy, swelling analysis and mechanical properties by texturometer. The morphology of the matrices showed large pores and foliaceous structure. In vivo testing, as well as the evaluation of acute dermal toxicity, was conducted using male Wistar rats. The tests indicated efficient collagen fiber production, improved skin repair and no signs of dermal toxicity. Thus, the hydrogel presents compatible properties for the controlled release of calendula extract used as a bandage to promote cicatrization. Full article
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19 pages, 4770 KiB  
Article
Age-Related Properties of Aquaponics-Derived Tilapia Skin (Oreochromis niloticus): A Structural and Compositional Study
by Nunzia Gallo, Alberta Terzi, Teresa Sibillano, Cinzia Giannini, Annalia Masi, Alessandro Sicuro, Federica Stella Blasi, Angelo Corallo, Antonio Pennetta, Giuseppe Egidio De Benedetto, Francesco Montagna, Alfonso Maffezzoli, Alessandro Sannino and Luca Salvatore
Int. J. Mol. Sci. 2023, 24(3), 1938; https://doi.org/10.3390/ijms24031938 - 18 Jan 2023
Cited by 2 | Viewed by 1899
Abstract
In the last two decades, fisheries and fish industries by-products have started to be recovered for the extraction of type I collagen because of issues related to the extraction of traditional mammalian tissues. In this work, special attention has been paid to by-products [...] Read more.
In the last two decades, fisheries and fish industries by-products have started to be recovered for the extraction of type I collagen because of issues related to the extraction of traditional mammalian tissues. In this work, special attention has been paid to by-products from fish bred in aquaponic plants. The valorization of aquaponic fish wastes as sources of biopolymers would make the derived materials eco-friendlier and attractive in terms of profitability and cost effectiveness. Among fish species, Nile Tilapia is the second-most farmed species in the world and its skin is commonly chosen as a collagen extraction source. However, to the best of our knowledge, no studies have been carried out to investigate, in depth, the age-related differences in fish skin with the final aim of selecting the most advantageous fish size for collagen extraction. In this work, the impact of age on the structural and compositional properties of Tilapia skin was evaluated with the aim of selecting the condition that best lends itself to the extraction of type I collagen for biomedical applications, based on the known fact that the properties of the original tissue have a significant impact on those of the final product. Performed analysis showed statistically significant age-related differences. In particular, an increase in skin thickness (+110 µm) and of wavy-like collagen fiber bundle diameter (+3 µm) besides their organization variation was observed with age. Additionally, a preferred collagen molecule orientation along two specific directions was revealed, with a higher fiber orientation degree according to age. Thermal analysis registered a shift of the endothermic peak (+1.7 °C) and an increase in the enthalpy (+3.3 J/g), while mechanical properties were found to be anisotropic, with an age-dependent brittle behavior. Water (+13%) and ash (+0.6%) contents were found to be directly proportional with age, as opposed to protein (−8%) and lipid (−10%) contents. The amino acid composition revealed a decrease in the valine, leucine, isoleucine, and threonine content and an increase in proline and hydroxyproline. Lastly, fatty acids C14:0, C15:0, C16:1, C18:2n6c, C18:3n6, C18:0, C20:3n3, and C23:0 were revealed to be upregulated, while C18:1n9c was downregulated with age. Full article
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12 pages, 1475 KiB  
Article
Ring-Opening Metathesis Polymerization and Related Olefin Metathesis Reactions in Benzotrifluoride as an Environmentally Advantageous Medium
by Ervin Kovács, Bence Balterer, Nguyen Anh Duc, Györgyi Szarka, Michael C. Owen, Attila Domján and Béla Iván
Int. J. Mol. Sci. 2023, 24(1), 671; https://doi.org/10.3390/ijms24010671 - 30 Dec 2022
Cited by 3 | Viewed by 1917
Abstract
A tremendous number of solvents, either as liquids or vapors, contaminate the environment on a daily basis worldwide. Olefin metathesis, which has been widely used as high-yielding protocols for ring-opening metathesis polymerization (ROMP), ring-closing metathesis (RCM), and isomerization reactions, is typically performed in [...] Read more.
A tremendous number of solvents, either as liquids or vapors, contaminate the environment on a daily basis worldwide. Olefin metathesis, which has been widely used as high-yielding protocols for ring-opening metathesis polymerization (ROMP), ring-closing metathesis (RCM), and isomerization reactions, is typically performed in toxic and volatile solvents such as dichloromethane. In this study, the results of our systematic experiments with the Grubbs G1, G2, and Hoveyda-Grubbs HG2 catalysts proved that benzotrifluoride (BTF) can replace dichloromethane (DCM) in these reactions, providing high yields and similar or even higher reaction rates in certain cases. The ROMP of norbornene resulted not only in high yields but also in polynorbornenes with a high molecular weight at low catalyst loadings. Ring-closing metathesis (RCM) experiments proved that, with the exception of the G1 catalyst, RCM occurs with similar high efficiencies in BTF as in DCM. It was found that isomerization of (Z)-but-2-ene-1,4-diyl diacetate with the G2 and HG2 catalysts proceeds at significantly higher initial rates in BTF than in DCM, leading to rapid isomerization with high yields in a short time. Overall, BTF is a suitable solvent for olefin metathesis, such as polymer syntheses by ROMP and the ring-closing and isomerization reactions. Full article
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17 pages, 6006 KiB  
Article
Exploring Saduria entomon (Crustacea Isopoda) as a New Source for Chitin and Chitosan Isolation
by Isabel Rodriguez-Veiga, Niuris Acosta, Inmaculada Aranaz and Aldona Dobrzycka-Krahel
Int. J. Mol. Sci. 2022, 23(24), 16125; https://doi.org/10.3390/ijms232416125 - 17 Dec 2022
Cited by 2 | Viewed by 1816
Abstract
Chitin and chitosan demand is growing very fast due to interest from industries such as pharmaceutical, cosmetic, agricultural and others. New sources for chitin and chitosan isolation are being extensively searched to fulfil this demand. In this paper, Saduria entomon a Baltic benthic [...] Read more.
Chitin and chitosan demand is growing very fast due to interest from industries such as pharmaceutical, cosmetic, agricultural and others. New sources for chitin and chitosan isolation are being extensively searched to fulfil this demand. In this paper, Saduria entomon a Baltic benthic crustacean, is evaluated as a source for chitin and chitosan isolation. Chitin and chitosan yield from S. entomon were 14.8 and 8.2%, respectively, in a similar range to other sources. Samples were characterized in terms of physicochemical properties (acetylation degree, molecular weight, thermal stability, and crystallinity) and two biological properties, antimicrobial activity and antioxidant activity were evaluated. Chitosan S. entomon exhibited antimicrobial activity against S. aureus but not against E. coli. An antioxidant activity of 20.98 TROLOX µmol equivalent/g polymer was detected for the chitosan sample. These properties are very promising for the use of this organism as a source for chitin and chitosan isolation in the biomedical field. Full article
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18 pages, 4566 KiB  
Article
Development of Methotrexate Complexes Endowed with New Biological Properties Envisioned for Musculoskeletal Regeneration in Rheumatoid Arthritis Environments
by Daniel Fernández-Villa, Rosa Ana Ramírez-Jiménez, Inmaculada Aranaz, Niuris Acosta, Blanca Vázquez-Lasa and Luis Rojo
Int. J. Mol. Sci. 2022, 23(17), 10054; https://doi.org/10.3390/ijms231710054 - 02 Sep 2022
Cited by 1 | Viewed by 1809
Abstract
Methotrexate (MTX) administration is the gold standard treatment for rheumatoid arthritis (RA), but its effects are limited to preventing the progression of the disease. Therefore, effective regenerative therapies for damaged tissues are still to be developed. In this regard, MTX complexes of general [...] Read more.
Methotrexate (MTX) administration is the gold standard treatment for rheumatoid arthritis (RA), but its effects are limited to preventing the progression of the disease. Therefore, effective regenerative therapies for damaged tissues are still to be developed. In this regard, MTX complexes of general molecular formula M(MTX)·xH2O, where M = Sr, Zn, or Mg, were synthesized and physicochemically characterized by TGA, XRD, NMR, ATR–FTIR, and EDAX spectroscopies. Characterization results demonstrated the coordination between the different cations and MTX via two monodentate bonds with the carboxylate groups of MTX. Cation complexation provided MTX with new bioactive properties such as increasing the deposition of glycosaminoglycans (GAGs) and alternative anti-inflammatory capacities, without compromising the immunosuppressant properties of MTX on macrophages. Lastly, these new complexes were loaded into spray-dried chitosan microparticles as a proof of concept that they can be encapsulated and further delivered in situ in RA-affected joints, envisioning them as a suitable alternative to oral MTX therapy. Full article
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14 pages, 4668 KiB  
Article
Influence of Clones on Relationship between Natural Rubber and Size of Rubber Particles in Latex
by Simin He, Fuquan Zhang, Fengshou Gu, Tianqi Zhao, Yanfang Zhao, Lusheng Liao and Xiaoxue Liao
Int. J. Mol. Sci. 2022, 23(16), 8880; https://doi.org/10.3390/ijms23168880 - 10 Aug 2022
Cited by 1 | Viewed by 1721
Abstract
IAN873, Dongfang93114 and Reyan73397, created through vegetative propagation for their high yield and excellent cold resistance, are major clones planted in China. In this work, latexes with rubber particles of the same size from these clones are separated from fresh natural rubber latex, [...] Read more.
IAN873, Dongfang93114 and Reyan73397, created through vegetative propagation for their high yield and excellent cold resistance, are major clones planted in China. In this work, latexes with rubber particles of the same size from these clones are separated from fresh natural rubber latex, and corresponding rubber films are prepared from each latex. The structure and components of each film are measured. This indicates that the characteristics of the rubbers obtained from latexes with similar particle sizes show some resembling trends among different clones, while for specific samples, those characteristics vary depending on the clone. The molecular weight is generally highest in IAN873 and lowest in Reyan73397. Rubber chains in small rubber particles are longer, and large rubber particles show a wider molecular weight distribution. The gel content of every sample from Reyan73397 is lower than the other two clones. The nitrogen content increases with the size of rubber particles in all clones. The ester content of small rubber particles in IAN873 and Reyan73397 is almost zero. Large rubber particles have more branching points formed via esters. This study provides a new perspective on the influence of clones on the relationship between characteristics of natural rubber and the size of rubber particles in natural rubber latex. Full article
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17 pages, 3744 KiB  
Article
Role of Combined Na2HPO4 and ZnCl2 in the Unprecedented Catalysis of the Sequential Pretreatment of Sustainable Agricultural and Agro-Industrial Wastes in Boosting Bioethanol Production
by Shaimaa Elyamny, Ali Hamdy, Rehab Ali and Hesham Hamad
Int. J. Mol. Sci. 2022, 23(3), 1777; https://doi.org/10.3390/ijms23031777 - 04 Feb 2022
Cited by 9 | Viewed by 2242
Abstract
Improper lignocellulosic waste disposal causes severe environmental pollution and health damage. Corn Stover (CS), agricultural, and aseptic packaging, Tetra Pak (TP) cartons, agro-industrial, are two examples of sustainable wastes that are rich in carbohydrate materials and may be used to produce valuable by-products. [...] Read more.
Improper lignocellulosic waste disposal causes severe environmental pollution and health damage. Corn Stover (CS), agricultural, and aseptic packaging, Tetra Pak (TP) cartons, agro-industrial, are two examples of sustainable wastes that are rich in carbohydrate materials and may be used to produce valuable by-products. In addition, attempts were made to enhance cellulose fractionation and improve enzymatic saccharification. In this regard, these two wastes were efficiently employed as substrates for bioethanol production. This research demonstrates the effect of disodium hydrogen phosphate (Na2HPO4) and zinc chloride (ZnCl2) (NZ) as a new catalyst on the development of the sequential pretreatment strategy in the noticeable enzymatic hydrolysis. Physico-chemical changes of the native and the pretreated sustainable wastes were evaluated by compositional analysis, scanning electron microscopy (SEM), X-ray diffractometry (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). These investigations showed major structural changes after the optimized sequential pretreatment. This pretreatment not only influences the delignification process, but also affects the functionalization of cellulose chemical structure. NZ released a higher glucose concentration (328.8 and 996.8 mg/dl) than that of ZnCl2 (Z), which released 203.8 and 846.8 mg/dl from CS and TP, respectively. This work led to the production of about 500 mg/dl of ethanol, which is promising and a competitor to other studies. These findings contribute to increasing the versatility in the reuse of agricultural and agro-industrial wastes to promote interaction areas of pollution prevention, industrialization, and clean energy production, to attain the keys of sustainable development goals. Full article
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13 pages, 17234 KiB  
Article
The Application of 2,6-Bis(4-Methoxybenzoyl)-Diaminopyridine in Solvent Extraction and Polymer Membrane Separation for the Recovery of Au(III), Ag(I), Pd(II) and Pt(II) Ions from Aqueous Solutions
by Daria Bożejewicz, Katarzyna Witt, Małgorzata A. Kaczorowska, Włodzimierz Urbaniak and Borys Ośmiałowski
Int. J. Mol. Sci. 2021, 22(17), 9123; https://doi.org/10.3390/ijms22179123 - 24 Aug 2021
Cited by 8 | Viewed by 1954
Abstract
The work describes the results of the first application of 2,6-bis(4-methoxybenzoyl)-diaminopyridine (L) for the recovery of noble metal ions (Au(III), Ag(I), Pd(II), Pt(II)) from aqueous solutions using two different separation processes: dynamic (classic solvent extraction) and static (polymer membranes). The stability [...] Read more.
The work describes the results of the first application of 2,6-bis(4-methoxybenzoyl)-diaminopyridine (L) for the recovery of noble metal ions (Au(III), Ag(I), Pd(II), Pt(II)) from aqueous solutions using two different separation processes: dynamic (classic solvent extraction) and static (polymer membranes). The stability constants of the complexes formed by the L with noble metal ions were determined using the spectrophotometry method. The results of the performed experiments clearly show that 2,6-bis(4-methoxybenzoyl)-diaminopyridine is an excellent extractant, as the recovery was over 99% for all studied noble metal ions. The efficiency of 2,6-bis(4-methoxybenzoyl)-diaminopyridine as a carrier in polymer membranes after 24 h of sorption was lower; the percentage of metal ions removal from the solutions (%Rs) decreased in following order: Ag(I) (94.89%) > Au(III) (63.46%) > Pt(II) (38.99%) > Pd(II) (23.82%). The results of the desorption processes carried out showed that the highest percentage of recovery was observed for gold and silver ions (over 96%) after 48 h. The results presented in this study indicate the potential practical applicability of 2,6-bis(4-methoxybenzoyl)-diaminopyridine in the solvent extraction and polymer membrane separation of noble metal ions from aqueous solutions (e.g., obtained as a result of WEEE leaching or industrial wastewater). Full article
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23 pages, 4360 KiB  
Article
Effect of Extreme Ultraviolet (EUV) Radiation and EUV Induced, N2 and O2 Based Plasmas on a PEEK Surface’s Physico-Chemical Properties and MG63 Cell Adhesion
by Joanna Czwartos, Bogusław Budner, Andrzej Bartnik, Przemysław Wachulak, Beata A. Butruk-Raszeja, Adam Lech, Tomasz Ciach and Henryk Fiedorowicz
Int. J. Mol. Sci. 2021, 22(16), 8455; https://doi.org/10.3390/ijms22168455 - 06 Aug 2021
Cited by 13 | Viewed by 2676
Abstract
Polyetheretherketone (PEEK), due to its excellent mechanical and physico-chemical parameters, is an attractive substitute for hard tissues in orthopedic applications. However, PEEK is hydrophobic and lacks surface-active functional groups promoting cell adhesion. Therefore, the PEEK surface must be modified in order to improve [...] Read more.
Polyetheretherketone (PEEK), due to its excellent mechanical and physico-chemical parameters, is an attractive substitute for hard tissues in orthopedic applications. However, PEEK is hydrophobic and lacks surface-active functional groups promoting cell adhesion. Therefore, the PEEK surface must be modified in order to improve its cytocompatibility. In this work, extreme ultraviolet (EUV) radiation and two low-temperature, EUV induced, oxygen and nitrogen plasmas were used for surface modification of polyetheretherketone. Polymer samples were irradiated with 100, 150, and 200 pulses at a 10 Hz repetition rate. The physical and chemical properties of EUV and plasma modified PEEK surfaces, such as changes of the surface topography, chemical composition, and wettability, were examined using atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and goniometry. The human osteoblast-like MG63 cells were used for the analysis of cell viability and cell adhesion on all modified PEEK surfaces. EUV radiation and two types of plasma treatment led to significant changes in surface topography of PEEK, increasing surface roughness and formation of conical structures. Additionally, significant changes in the chemical composition were found and were manifested with the appearance of new functional groups, incorporation of nitrogen atoms up to ~12.3 at.% (when modified in the presence of nitrogen), and doubling the oxygen content up to ~25.7 at.% (when modified in the presence of oxygen), compared to non-modified PEEK. All chemically and physically changed surfaces demonstrated cyto-compatible and non-cytotoxic properties, an enhancement of MG63 cell adhesion was also observed. Full article
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13 pages, 3543 KiB  
Article
Procoagulant and Antimicrobial Effects of Chitosan in Wound Healing
by Chih-Hsin Wang, Juin-Hong Cherng, Chuan-Chieh Liu, Tong-Jing Fang, Zhi-Jie Hong, Shu-Jen Chang, Gang-Yi Fan and Sheng-Der Hsu
Int. J. Mol. Sci. 2021, 22(13), 7067; https://doi.org/10.3390/ijms22137067 - 30 Jun 2021
Cited by 32 | Viewed by 3753
Abstract
Chitosan, a polysaccharide derived from chitin, has excellent wound healing properties, including intrinsic antimicrobial and hemostatic activities. This study investigated the effectiveness of chitosan dressing and compared it with that of regular gauze dressing in controlling clinically surgical bleeding wounds and profiled the [...] Read more.
Chitosan, a polysaccharide derived from chitin, has excellent wound healing properties, including intrinsic antimicrobial and hemostatic activities. This study investigated the effectiveness of chitosan dressing and compared it with that of regular gauze dressing in controlling clinically surgical bleeding wounds and profiled the community structure of the microbiota affected by these treatments. The dressings were evaluated based on biocompatibility, blood coagulation factors in rat, as well as antimicrobial and procoagulant activities, and the microbial phylogenetic profile in patients with abdominal surgical wounds. The chitosan dressing exhibited a uniformly fibrous morphology with a large surface area and good biocompatibility. Compared to regular gauze dressing, the chitosan dressing accelerated platelet aggregation, indicated by the lower ratio of prothrombin time and activated partial thromboplastin time, and had outstanding blood absorption ability. Adenosine triphosphate assay results revealed that the chitosan dressing inhibited bacterial growth up to 8 d post-surgery. Moreover, 16S rRNA-based sequencing revealed that the chitosan dressing effectively protected the wound from microbial infection and promoted the growth of probiotic microbes, thereby improving skin immunity and promoting wound healing. Our findings suggest that chitosan dressing is an effective antimicrobial and procoagulant and promotes wound repair by providing a suitable environment for beneficial microbiota. Full article
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Review

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22 pages, 1548 KiB  
Review
Chitosan–Hydroxycinnamic Acids Conjugates: Emerging Biomaterials with Rising Applications in Biomedicine
by Doddy Denise Ojeda-Hernández, Alejandro A. Canales-Aguirre, Jordi A. Matias-Guiu, Jorge Matias-Guiu, Ulises Gómez-Pinedo and Juan Carlos Mateos-Díaz
Int. J. Mol. Sci. 2022, 23(20), 12473; https://doi.org/10.3390/ijms232012473 - 18 Oct 2022
Cited by 4 | Viewed by 2223
Abstract
Over the past thirty years, research has shown the huge potential of chitosan in biomedical applications such as drug delivery, tissue engineering and regeneration, cancer therapy, and antimicrobial treatments, among others. One of the major advantages of this interesting polysaccharide is its modifiability, [...] Read more.
Over the past thirty years, research has shown the huge potential of chitosan in biomedical applications such as drug delivery, tissue engineering and regeneration, cancer therapy, and antimicrobial treatments, among others. One of the major advantages of this interesting polysaccharide is its modifiability, which facilitates its use in tailor-made applications. In this way, the molecular structure of chitosan has been conjugated with multiple molecules to modify its mechanical, biological, or chemical properties. Here, we review the conjugation of chitosan with some bioactive molecules: hydroxycinnamic acids (HCAs); since these derivatives have been probed to enhance some of the biological effects of chitosan and to fine-tune its characteristics for its application in the biomedical field. First, the main characteristics of chitosan and HCAs are presented; then, the currently employed conjugation strategies between chitosan and HCAs are described; and, finally, the studied biomedical applications of these derivatives are discussed to present their limitations and advantages, which could lead to proximal therapeutic uses. Full article
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38 pages, 378 KiB  
Review
Polymeric Gels and Their Application in the Treatment of Psoriasis Vulgaris: A Review
by Agnieszka Kulawik-Pióro and Małgorzata Miastkowska
Int. J. Mol. Sci. 2021, 22(10), 5124; https://doi.org/10.3390/ijms22105124 - 12 May 2021
Cited by 27 | Viewed by 8528
Abstract
Psoriasis is a chronic skin disease, and it is especially characterized by the occurrence of red, itchy, and scaly eruptions on the skin. The quality of life of patients with psoriasis is decreased because this disease remains incurable, despite the rapid progress of [...] Read more.
Psoriasis is a chronic skin disease, and it is especially characterized by the occurrence of red, itchy, and scaly eruptions on the skin. The quality of life of patients with psoriasis is decreased because this disease remains incurable, despite the rapid progress of therapeutic methods and the introduction of many innovative antipsoriatic drugs. Moreover, many patients with psoriasis are dissatisfied with their current treatment methods and the form with which the drug is applied. The patients complain about skin irritation, clothing stains, unpleasant smell, or excessive viscosity of the preparation. The causes of these issues should be linked with little effectiveness of the therapy caused by low permeation of the drug into the skin, as well as patients’ disobeying doctors’ recommendations, e.g., concerning regular application of the preparation. Both of these factors are closely related to the physicochemical form of the preparation and its rheological and mechanical properties. To improve the quality of patients’ lives, it is important to gain knowledge about the specific form of the drug and its effect on the safety and efficacy of a therapy as well as the patients’ comfort during application. Therefore, we present a literature review and a detailed analysis of the composition, rheological properties, and mechanical properties of polymeric gels as an alternative to viscous and greasy ointments. We discuss the following polymeric gels: hydrogels, oleogels, emulgels, and bigels. In our opinion, they have many characteristics (i.e., safety, effectiveness, desired durability, acceptance by patients), which can contribute to the development of an effective and, at the same time comfortable, method of local treatment of psoriasis for patients. Full article
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