Um die anderen Arten von Veröffentlichungen zu diesem Thema anzuzeigen, folgen Sie diesem Link: Composite Hydrogels.
Zeitschriftenartikel zum Thema „Composite Hydrogels“
Geben Sie eine Quelle nach APA, MLA, Chicago, Harvard und anderen Zitierweisen an
Machen Sie sich mit Top-50 Zeitschriftenartikel für die Forschung zum Thema "Composite Hydrogels" bekannt.
Neben jedem Werk im Literaturverzeichnis ist die Option "Zur Bibliographie hinzufügen" verfügbar. Nutzen Sie sie, wird Ihre bibliographische Angabe des gewählten Werkes nach der nötigen Zitierweise (APA, MLA, Harvard, Chicago, Vancouver usw.) automatisch gestaltet.
Sie können auch den vollen Text der wissenschaftlichen Publikation im PDF-Format herunterladen und eine Online-Annotation der Arbeit lesen, wenn die relevanten Parameter in den Metadaten verfügbar sind.
Sehen Sie die Zeitschriftenartikel für verschiedene Spezialgebieten durch und erstellen Sie Ihre Bibliographie auf korrekte Weise.
1
Wu, Hongyi, Nitong Bu, Jie Chen, Yuanyuan Chen, Runzhi Sun, Chunhua Wu und Jie Pang. „Construction of Konjac Glucomannan/Oxidized Hyaluronic Acid Hydrogels for Controlled Drug Release“. Polymers 14, Nr. 5 (25.02.2022): 927. http://dx.doi.org/10.3390/polym14050927.
Der volle Inhalt der QuelleAnnotation:
Konjac glucomannan (KGM) hydrogel has favorable gel-forming abilities, but its insufficient swelling capacity and poor control release characteristics limit its application. Therefore, in this study, oxidized hyaluronic acid (OHA) was used to improve the properties of KGM hydrogel. The influence of OHA on the structure and properties of KGM hydrogels was evaluated. The results show that the swelling capacity and rheological properties of the composite hydrogels increased with OHA concentration, which might be attributed to the hydrogen bond between the KGM and OHA, resulting in a compact three-dimensional gel network structure. Furthermore, epigallocatechin gallate (EGCG) was efficiently loaded into the KGM/OHA composite hydrogels and liberated in a sustained pattern. The cumulative EGCG release rate of the KGM/OHA hydrogels was enhanced by the increasing addition of OHA. The results show that the release rate of composite hydrogel can be controlled by the content of OHA. These results suggest that OHA has the potential to improve the properties and control release characteristics of KGM hydrogels.
2
Zheng, Jianuo, Yunping Wang, Yuwen Wang, Ruiping Duan und Lingrong Liu. „Gelatin/Hyaluronic Acid Photocrosslinked Double Network Hydrogel with Nano-Hydroxyapatite Composite for Potential Application in Bone Repair“. Gels 9, Nr. 9 (13.09.2023): 742. http://dx.doi.org/10.3390/gels9090742.
Der volle Inhalt der QuelleAnnotation:
The application of hydrogels in bone repair is limited due to their low mechanical strength. Simulating bone extracellular matrix, methylacrylylated gelatin (GelMA)/methylacrylylated hyaluronic acid (HAMA)/nano-hydroxyapatite(nHap) composite hydrogels were prepared by combining the double network strategy and composite of nHap in this study. The precursor solutions of the composite hydrogels were injectable due to their shear thinning property. The compressive elastic modulus of the composite hydrogel was significantly enhanced, the fracture strength of the composite hydrogel nearly reached 1 MPa, and the composite hydrogel retained its high water content at above 88%. The composite hydrogels possess good compatibility with BMSCS and have the potential to be used as injectable hydrogels for bone defect treatment.
3
Nie, Lei, Pengbo Chang, Meng Sun, Haojie Huo, Chunxia Zhang, Chingching Ji, Xiaoyan Wei, Qiuju Zhou, Peiyin Guo und Hongyu Yuan. „Composite Hydrogels with the Simultaneous Release of VEGF and MCP-1 for Enhancing Angiogenesis for Bone Tissue Engineering Applications“. Applied Sciences 8, Nr. 12 (01.12.2018): 2438. http://dx.doi.org/10.3390/app8122438.
Der volle Inhalt der QuelleAnnotation:
Rapid new microvascular network induction was critical for bone regeneration, which required the spatiotemporal delivery of growth factors and transplantation of endothelial cells. In this study, the linear poly(d,l-lactic-co-glycolic acid)-b-methoxy poly(ethylene glycol) (PLGA-mPEG) block copolymer microspheres were prepared for simultaneously delivering vascular endothelial growth factor (VEGF) and monocyte chemotactic protein-1 (MCP-1). Then, vascular endothelial cells (VECs) with growth factor loaded microspheres were composited into a star-shaped PLGA-mPEG block copolymer solution. After this, composite hydrogel (microspheres ratio: 5 wt%) was formed by increasing the temperature to 37 °C. The release profiles of VEGF and MCP-1 from composite hydrogels in 30 days were investigated to confirm the different simultaneous delivery systems. The VECs exhibited a good proliferation in the composite hydrogels, which proved that the composite hydrogels had a good cytocompatibility. Furthermore, in vivo animal experiments showed that the vessel density and the mean vessel diameters increased over weeks after the composite hydrogels were implanted into the necrosis site of the rabbit femoral head. The above results suggested that the VECs-laden hydrogel composited with the dual-growth factor simultaneous release system has the potential to enhance angiogenesis in bone tissue engineering.
4
Elvitigala, Kelum Chamara Manoj Lakmal, Wildan Mubarok und Shinji Sakai. „Human Umbilical Vein Endothelial Cells Form a Network on a Hyaluronic Acid/Gelatin Composite Hydrogel Moderately Crosslinked and Degraded by Hydrogen Peroxide“. Polymers 14, Nr. 22 (20.11.2022): 5034. http://dx.doi.org/10.3390/polym14225034.
Der volle Inhalt der QuelleAnnotation:
The study of the capillary-like network formation of human umbilical vein endothelial cells (HUVECs) in vitro is important for understanding the factors that promote or inhibit angiogenesis. Here, we report the behavior of HUVECs on the composite hydrogels containing hyaluronic acid (HA) and gelatin with different degrees of degradation, inducing the different physicochemical properties of the hydrogels. The hydrogels were obtained through horseradish peroxidase (HRP)-catalyzed hydrogelation consuming hydrogen peroxide (H2O2, 16 ppm) supplied from the air, and the degradation degree was tuned by altering the exposure time to the air. The HUVECs on the composite hydrogel with intermediate stiffness (1.2 kPa) obtained through 120 min of the exposure were more elongated than those on the soft (0.4 kPa) and the stiff (2.4 kPa) composite hydrogels obtained through 15 min and 60 min of the exposure, respectively. In addition, HUVECs formed a capillary-like network only on the stiff composite hydrogel although those on the hydrogels with comparable stiffness but containing gelatin alone or alginate instead of HA did not form the network. These results show that the HA/gelatin composite hydrogels obtained through the H2O2-mediated crosslinking and degradation could be a tool for studies using HUVECs to understand the promotion and inhibition of angiogenesis.
5
Murshid, Nimer, Omar Mouhtady, Mahmoud Abu-samha, Emil Obeid, Yahya Kharboutly, Hamdi Chaouk, Jalal Halwani und Khaled Younes. „Metal Oxide Hydrogel Composites for Remediation of Dye-Contaminated Wastewater: Principal Component Analysis“. Gels 8, Nr. 11 (30.10.2022): 702. http://dx.doi.org/10.3390/gels8110702.
Der volle Inhalt der QuelleAnnotation:
Water pollution is caused by multiple factors, such as industrial dye wastewater. Dye-contaminated water can be treated using hydrogels as adsorbent materials. Recently, composite hydrogels containing metal oxide nanoparticles (MONPs) have been used extensively in wastewater remediation. In this study, we use a statistical and artificial intelligence method, based on principal component analysis (PCA) with different applied parameters, to evaluate the adsorption efficiency of 27 different MONP composite hydrogels for wastewater dye treatment. PCA showed that the hydrogel composites CTS@Fe3O4, PAAm/TiO2, and PEGDMA-rGO/Fe3O4@cellulose should be used in situations involving high pH, time to reach equilibrium, and adsorption capacity. However, as the composites PAAm-co-AAc/TiO2, PVPA/Fe3O4@SiO2, PMOA/ATP/Fe3O4, and PVPA/Fe3O4@SiO2, are preferred when all physical and chemical properties investigated have low magnitudes. To conclude, PCA is a strong method for highlighting the essential factors affecting hydrogel composite selection for dye-contaminated water treatment.
6
Huang, Yu-Chao, Pei-Wen Lin, Wen-Jian Qiu und Ta-I. Yang. „AMPHIPHILIC POLYMER-ASSISTED SYNTHESIS OF HYDROXYAPATITE PARTICLES AND THEIR INFLUENCE ON THE RHEOLOGICAL AND MECHANICAL PROPERTIES OF THERMOSENSITIVE HYDROGELS“. Biomedical Engineering: Applications, Basis and Communications 28, Nr. 02 (April 2016): 1650013. http://dx.doi.org/10.4015/s1016237216500137.
Der volle Inhalt der QuelleAnnotation:
Polymeric composite materials hold promise for versatile advanced applications. Of utmost importance for these applications is incorporating inorganic particles within polymer matrices which lead to multifunctional polymeric composites with desired functions. Specifically, thermosensitive polymeric hydrogels incorporating particle fillers have elicited widespread interest because of promising applications in drug delivery, tissue engineering, and medical devices. Although these materials are frequently discussed in many research fields, there are no decisive conclusions reported in literature, showing how the particle filler affects the rheological and mechanical behaviors of the resulting hydrogels. In this research, hydroxyapatite (HAp) bioceramics with definable morphologies were synthesized in order to reveal their effects on the resulting properties of HAp/polymer composite hydrogels. HAp particles with spherical, sheet-like and rod-like shapes were prepared with assistance by adding amphiphilic surfactant, poly(ethylene oxide)-b-poly(propylene oxide)-b-poly(ethylene oxide) in synthesis. Thermosensitive composite hydrogels with controllable rheological and mechanical properties were thus developed by incorporating HAp particles into poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PEG-PLGA) hydrogel. Experimental results revealed that the rheological and mechanical properties of the resultant HAp/PEG-PLGA composite hydrogel not only influenced by the added HAp particle amount, but also by the particle morphology and interactions between particles and hydrogels. The findings from this research provide a critical guideline for designing thermosensitive composite hydrogels with required rheological and mechanical properties.
7
Ye, Jing, Gang Yang, Jing Zhang, Zhenghua Xiao, Ling He, Han Zhang und Qi Liu. „Preparation and characterization of gelatin-polysaccharide composite hydrogels for tissue engineering“. PeerJ 9 (15.03.2021): e11022. http://dx.doi.org/10.7717/peerj.11022.
Der volle Inhalt der QuelleAnnotation:
Background Tissue engineering, which involves the selection of scaffold materials, presents a new therapeutic strategy for damaged tissues or organs. Scaffold design based on blends of proteins and polysaccharides, as mimicry of the native extracellular matrix, has recently become a valuable strategy for tissue engineering. Objective This study aimed to construct composite hydrogels based on natural polymers for tissue engineering. Methods Composite hydrogels based on blends of gelatin with a polysaccharide component (chitosan or alginate) were produced and subsequently enzyme crosslinked. The other three hydrogels, chitosan hydrogel, sodium alginate hydrogel, and microbial transglutaminase-crosslinked gelatin (mTG/GA) hydrogel were also prepared. All hydrogels were evaluated for in vitro degradation property, swelling capacity, and mechanical property. Rat adipose-derived stromal stem cells (ADSCs) were isolated and seeded on (or embedded into) the above-mentioned hydrogels. The morphological features of ADSCs were observed and recorded. The effects of the hydrogels on ADSC survival and adhesion were investigated by immunofluorescence staining. Cell proliferation was tested by thiazolyl blue tetrazolium bromide (MTT) assay. Results Cell viability assay results showed that the five hydrogels are not cytotoxic. The mTG/GA and its composite hydrogels showed higher compressive moduli than the single-component chitosan and alginate hydrogels. MTT assay results showed that ADSCs proliferated better on the composite hydrogels than on the chitosan and alginate hydrogels. Light microscope observation and cell cytoskeleton staining showed that hydrogel strength had obvious effects on cell growth and adhesion. The ADSCs seeded on chitosan and alginate hydrogels plunged into the hydrogels and could not stretch out due to the low strength of the hydrogel, whereas cells seeded on composite hydrogels with higher elastic modulus, could spread out, and grew in size. Conclusion The gelatin-polysaccharide composite hydrogels could serve as attractive biomaterials for tissue engineering due to their easy preparation and favorable biophysical properties.
8
Ahmad, Faheem, Bushra Mushtaq, Faaz Ahmed Butt, Muhammad Sohail Zafar, Sheraz Ahmad, Ali Afzal, Yasir Nawab, Abher Rasheed und Zeynep Ulker. „Synthesis and Characterization of Nonwoven Cotton-Reinforced Cellulose Hydrogel for Wound Dressings“. Polymers 13, Nr. 23 (25.11.2021): 4098. http://dx.doi.org/10.3390/polym13234098.
Der volle Inhalt der QuelleAnnotation:
Hydrogels wound dressings have enormous advantages due to their ability to absorb high wound exudate, capacity to load drugs, and provide quick pain relief. The use of hydrogels as wound dressings in their original form is a considerable challenge, as these are difficult to apply on wounds without support. Therefore, the incorporation of polymeric hydrogels with a certain substrate is an emerging field of interest. The present study fabricated cellulose hydrogel using the sol–gel technique and reinforced it with nonwoven cotton for sustainable wound dressing application. The nonwoven cotton was immersed inside the prepared solution of cellulose and heated at 50 °C for 2 h to form cellulose hydrogel–nonwoven cotton composites and characterized for a range of properties. In addition, the prepared hydrogel composite was also loaded with titania particles to attain antibacterial properties. The Fourier transform infrared spectroscopy and scanning electron microscopy confirmed the formation of cellulose hydrogel layers inside the nonwoven cotton structure. The fabricated composite hydrogels showed good moisture management and air permeability, which are essential for comfortable wound healing. The wound exudate testing revealed that the fluid absorptive capacity of cellulose hydrogel nonwoven cotton composite was improved significantly in comparison to pure nonwoven cotton. The results reveal the successful hydrogel formation, having excellent absorbing, antimicrobial, and sustainable properties.
9
Pavlyuchenko, V. N., und S. S. Ivanchev. „Composite polymer hydrogels“. Polymer Science Series A 51, Nr. 7 (Juli 2009): 743–60. http://dx.doi.org/10.1134/s0965545x09070013.
Der volle Inhalt der Quelle
10
Ščeglovs, Artemijs, und Kristine Salma-Ancane. „Novel Hydrogels and Composite Hydrogels Based on ԑ-Polylysine, Hyaluronic Acid and Hydroxyapatite“. Key Engineering Materials 850 (Juni 2020): 242–48. http://dx.doi.org/10.4028/www.scientific.net/kem.850.242.
Der volle Inhalt der QuelleAnnotation:
At this work hydrogel and composite hydrogel systems based on ԑ-polylysine (EPL), hyaluronic acid (HA) and nanocrystalline hydroxyapatite (nHAp) were synthesized via chemical cross-linking method followed by in situ precipitation of nHAp into hydrogel copolymer matrix. Molecular structure, phase composition and morphology of EPL-HA and EPL-HA/nHAp systems were investigated using Fourier transform infrared spectroscopy (FTIR), X-ray powder diffractometry (XRD) and scanning electron microscopy (SEM). The fabricated hydrogels and composite hydrogels were evaluated by hydrogels characteristics such as gel fraction and swelling behavior. This study provides a new insight to develop cutting-edge bioactive hydrogels and composite hydrogels for bone tissue engineering as injectable biomaterials due to beneficial properties of system components.
11
Zinchenko, О. V., V. D. Ezhova und A. L. Tolstov. „SILICON-CONTAINING OLIGOMERIC AZOINITIATORS IN THE SYNTHESIS OF BLOCK COPOLYMERS“. Polymer journal 43, Nr. 2 (09.06.2021): 133–42. http://dx.doi.org/10.15407/polymerj.43.02.133.
Der volle Inhalt der QuelleAnnotation:
A solvothermal synthetic pathway and functional polymer styabilizers was used for synthesis of fine silver structures of different architecture. Using polyvinylpyrrolidone as a stabilizer silver micronized wires with a diameter of 3,8–4,2 μm and aspect ratio of up to 30 were prepared. XRD technique was applied for qualitative determination of silver metal structures. New thermoresponse composite hydrogels with a structure of semi-IPNs were prepared from cross-linked polyvinyl alcohol, linear highly hydrophilic poly(2-ethyl-2-oxazoline) (PEtOx) and as-synthesized silver micro-sized wires. Effect of a structure and a composition of the polymer matrix, and inorganic anisotropic filler on structure arrangement of composite hydrogels were evaluated by DMA studies. A presence of linear hydrophilic PEtOx and anisotropic metal filler in PVA matrix reduces storage modulus Е’ from 275 to 222–230 MPa and increases loss modulus Е” up to 45,5 MPa at room temperature measurements that partially initiated by poor structuration ability of the composites under high solvation level of polymer matrices. Increasing temperature leads to redistribution of hydrogen bonds network and hybridization of PVA nad PEtOx macrochains and enhances energy dissipation ability of unfilled hydrogel. A filler due to conjugation with amine-functionalized PEtOx chains and its localization closed to a surface of metal supresses polymer-polymer interactions and elasticity parameters of composite matrix drops down. As a result, diffusion and permeability coefficients of composite hydrogels reaches 1,06–1,52·10–9 cm2/s and 0,83–1,09·10-9 g/(cm·s), respectively, that higher in comparison with cross-linked PVA matrices. A presence of hydrogen bonds of different energy in hydrogels provides an appearance of multiple relaxation transitions due to different macrochain mobility in a bulk of polymer matrix. Differences of temperature interval of LCTS for hydrogels were found from analysis Е”(T)/dT (62–70 °С) and Δχ(T)/dT (67–70 °С) dependencies are interrelated with kinetic pecularities of diffusion processes that are able to suppress a phase separation at the temperatures closed to LCTS. Phase inversion processes for hydrogel containing 5 % of PEtOx at LCTS are accompanied by desorption of 32–73 % of sorbate. Moreover, thermoresponsive properties of the hydrogels filled with metallic silver wires are higher than that of the unfilled semi-IPNs.
12
Wang, Hongcai, Ruhong Yin, Xiuqiong Chen, Ting Wu, Yanan Bu, Huiqiong Yan und Qiang Lin. „Construction and Evaluation of Alginate Dialdehyde Grafted RGD Derivatives/Polyvinyl Alcohol/Cellulose Nanocrystals IPN Composite Hydrogels“. Molecules 28, Nr. 18 (19.09.2023): 6692. http://dx.doi.org/10.3390/molecules28186692.
Der volle Inhalt der QuelleAnnotation:
To enhance the mechanical strength and cell adhesion of alginate hydrogel, making it satisfy the requirements of an ideal tissue engineering scaffold, the grafting of Arg-Gly-Asp (RGD) polypeptide sequence onto the alginate molecular chain was conducted by oxidation of sodium periodate and subsequent reduction amination of 2-methylpyridine borane complex (2-PBC) to synthesize alginate dialdehyde grafted RGD derivatives (ADA-RGD) with good cellular affinity. The interpenetrating network (IPN) composite hydrogels of alginate/polyvinyl alcohol/cellulose nanocrystals (ALG/PVA/CNCs) were fabricated through a physical mixture of ion cross-linking of sodium alginate (SA) with hydroxyapatite/D-glucono-δ-lactone (HAP/GDL), and physical cross-linking of polyvinyl alcohol (PVA) by a freezing/thawing method, using cellulose nanocrystals (CNCs) as the reinforcement agent. The effects of the addition of CNCs and different contents of PVA on the morphology, thermal stability, mechanical properties, swelling, biodegradability, and cell compatibility of the IPN composite hydrogels were investigated, and the effect of RGD grafting on the biological properties of the IPN composite hydrogels was also studied. The resultant IPN ALG/PVA/CNCs composite hydrogels exhibited good pore structure and regular 3D morphology, whose pore size and porosity could be regulated by adjusting PVA content and the addition of CNCs. By increasing the PVA content, the number of physical cross-linking points in PVA increased, resulting in greater stress support for the IPN composite hydrogels of ALG/PVA/CNCs and consequently improving their mechanical characteristics. The creation of the IPN ALG/PVA/CNCs composite hydrogels’ physical cross-linking network through intramolecular or intermolecular hydrogen bonding led to improved thermal resistance and reduced swelling and biodegradation rate. Conversely, the ADA-RGD/PVA/CNCs IPN composite hydrogels exhibited a quicker degradation rate, attributed to the elimination of ADA-RGD by alkali. The results of the in vitro cytocompatibility showed that ALG/0.5PVA/0.3%CNCs and ADA-RGD/PVA/0.3%CNCs composite hydrogels showed better proliferative activity in comparison with other composite hydrogels, while ALG/PVA/0.3%CNCs and ADA-RGD/PVA/0.3%CNCs composite hydrogels displayed obvious proliferation effects, indicating that PVA, CNCs, and ADA-RGD with good biocompatibility were conducive to cell proliferation and differentiation for the IPN composite hydrogels.
13
Peng, Rui, Huilong Yu, Chungui Du, Jingjing Zhang, Ailian Hu, Qi Li, Yating Hua, Hongzhi Liu und Shimin Chu. „Preparation of uniformly dispersed N-isopropylacryl-amide/acrylic acid/nanosilver composite hydrogel and its anti-mold properties“. BioResources 16, Nr. 1 (20.11.2020): 441–54. http://dx.doi.org/10.15376/biores.16.1.441-454.
Der volle Inhalt der QuelleAnnotation:
To overcome the agglomeration tendency of nanosilver composite hydrogels and to improve their anti-mold properties, a method of preparing N-isopropylacrylamide/acrylic acid/nanosilver composite hydrogel was developed using the free radical polymerization method. The composite hydrogel was characterized via infrared spectroscopy, dynamic light scattering, transmission electron microscopy, and X-ray photoelectron spectroscopy in order to explore the effects of the acrylic acid content on particle size and dispersion properties of the composite hydrogels. The elemental composition, microstructure, and anti-mold properties of the bamboo strips treated with the composite hydrogel were also determined. The results showed that the composite hydrogel prepared using the novel method described in this study had good dispersity. Composite hydrogels with the smallest particle size and optimized dispersion were produced when AAc concentration was 0.64 µL/mL. The composite hydrogel effectively filled and covered the bamboo cells after treatment. Moreover, it displayed good anti-mold properties as well as retaining the color of the bamboo.
14
Wang, Boxiang, Song Zhang, Yifan Wang, Bo Si, Dehong Cheng, Li Liu und Yanhua Lu. „Regenerated Antheraea pernyi Silk Fibroin/Poly(N-isopropylacrylamide) Thermosensitive Composite Hydrogel with Improved Mechanical Strength“. Polymers 11, Nr. 2 (11.02.2019): 302. http://dx.doi.org/10.3390/polym11020302.
Der volle Inhalt der QuelleAnnotation:
At present, Antheraea pernyi silk fibroin (ASF) has attracted research efforts to investigate it as a raw material for fabrication of biomedical devices because of its superior cytocompatibility. Nevertheless, native ASF is not easily processed into a hydrogel without any crosslinking agent, and a single hydrogel shows poor mechanical properties. In this paper, a series of ASF/poly (N-isopropylacrylamide) (PNIPAAm) composite hydrogels with different ASF contents were manufactured by a simple in situ polymerization method without any crosslinking agent. Meanwhile, the structures, morphologies and thermal properties of composite hydrogels were investigated by XRD, FTIR, SEM, DSC and TGA, respectively. The results indicate that the secondary structure of silk in the composite hydrogel can be controlled by changing the ASF content and the thermal stability of composite hydrogels is enhanced with an increase in crystalline structure. The composite hydrogels showed similar lower critical solution temperatures (LCST) at about 32 °C, which matched well with the LCST of PNIPAAm. Finally, the obtained thermosensitive composite hydrogels exhibited enhanced mechanical properties, which can be tuned by varying the content of ASF. This strategy to prepare an ASF-based responsive composite hydrogel with enhanced mechanical properties represents a valuable route for developing the fields of ASF, and, furthermore, their attractive applications can meet the needs of different biomaterial fields.
15
Chai, Weihong, Rongbin Yang, Jiayi Zhou und Qinghua Wei. „Performance Comparison of PVA/SA Composite Hydrogels for 3D Printing of Cartilage Scaffolds with Different Compositions“. Journal of Physics: Conference Series 2437, Nr. 1 (01.01.2023): 012042. http://dx.doi.org/10.1088/1742-6596/2437/1/012042.
Der volle Inhalt der QuelleAnnotation:
Abstract Physical blend is the method always used to modify the properties of composite hydrogels for 3D printing in tissue engineering. In this paper, polyvinyl alcohol (PVA) blending with sodium alginate (SA) was applied to enhance the mechanical properties of SA. The PVA/SA blending hydrogels with different components (5:5, 4:6, 3:7, 2:8, 1:9, and 0:10) were prepared through cross-linking method, and their properties were studied from microstructure, mechanical property, hydrophilicity, and printability, so the optimal composition ratio of the composite hydrogel can be selected for 3D printing cartilage scaffold. Results show that with PVA increasing in composite hydrogel, the pore size of the composite hydrogel becomes smaller and more even. The tensile strength and toughness of PVA/SA hydrogels increased firstly and then decreased with the increase of PVA content, and the composite hydrogel of 2PVA/8AS has the best tensile strength. Moreover, the water content and printability of hydrogels decrease with the increase of PVA, which is in good agreement with the pore structures of hydrogels. Based on the above results, we believe that 8AS/2PVA blend hydrogel is the most suitable for 3D printing cartilage scaffolds.
16
Gu, Liling, Tao Li, Xiongbo Song, Xianteng Yang, Senlei Li, Long Chen, Pingju Liu, Xiaoyuan Gong, Cheng Chen und Li Sun. „Preparation and characterization of methacrylated gelatin/bacterial cellulose composite hydrogels for cartilage tissue engineering“. Regenerative Biomaterials 7, Nr. 2 (19.12.2019): 195–202. http://dx.doi.org/10.1093/rb/rbz050.
Der volle Inhalt der QuelleAnnotation:
Abstract Methacrylated gelatin (GelMA)/bacterial cellulose (BC) composite hydrogels have been successfully prepared by immersing BC particles in GelMA solution followed by photo-crosslinking. The morphology of GelMA/BC hydrogel was examined by scanning electron microscopy and compared with pure GelMA. The hydrogels had very well interconnected porous network structure, and the pore size decreased from 200 to 10 µm with the increase of BC content. The composite hydrogels were also characterized by swelling experiment, X-ray diffraction, thermogravimetric analysis, rheology experiment and compressive test. The composite hydrogels showed significantly improved mechanical properties compared with pure GelMA. In addition, the biocompatility of composite hydrogels were preliminarily evaluated using human articular chondrocytes. The cells encapsulated within the composite hydrogels for 7 days proliferated and maintained the chondrocytic phenotype. Thus, the GelMA/BC composite hydrogels might be useful for cartilage tissue engineering.
17
Yuan, Kun, Xiao Fang Wang, Yuan Cheng Zhu und Guo Fang Zuo. „Preparation of the Microsphere-Sized Poly(N-Isopropylacrylamide) Hydrogel Dispersed in Poly(Vinyl Alcohol) Matrix and its Thermo-Responsive Releasing Behavior“. Advanced Materials Research 311-313 (August 2011): 2084–88. http://dx.doi.org/10.4028/www.scientific.net/amr.311-313.2084.
Der volle Inhalt der QuelleAnnotation:
A novel thermo-responsive microsphere-sized poly(N-isopropylacrylamide) (PNIPAm) composite hydrogels were prepared by gelation of poly(vinyl alcohol) (PVA) solution containing ultra-fine CaCO3, then treated with 2wt% glutaraldehyde solution, sequencely with HCl acid, and PVA matrix with microsphere-sized pores obtained. The internal pores of the dry PVA matrix were filled with PNIPAm hydrogels to give a thermo-responsive composite hydrogels for drug carrier. The composite hydrogel was characterized via scanning electron microscopy (SEM), temperature dependence of equilibrium swelling ratio in water of the composite hydrogels was also investigated. Rhodamine B (RB) was loaded to the composite hydrogels for release study.
18
Liu, Shih-Ming, Wen-Cheng Chen, Chia-Ling Ko, Hsu-Ting Chang, Ya-Shun Chen, Ssu-Meng Haung, Kai-Chi Chang und Jian-Chih Chen. „In Vitro Evaluation of Calcium Phosphate Bone Cement Composite Hydrogel Beads of Cross-Linked Gelatin-Alginate with Gentamicin-Impregnated Porous Scaffold“. Pharmaceuticals 14, Nr. 10 (29.09.2021): 1000. http://dx.doi.org/10.3390/ph14101000.
Der volle Inhalt der QuelleAnnotation:
Calcium phosphate bone cement (CPC) is in the form of a paste, and its special advantage is that it can repair small and complex bone defects. In the case of open wounds, tissue debridement is necessary before tissue repair and the subsequent control of wound infection; therefore, CPC composite hydrogel beads containing antibiotics provide an excellent option to fill bone defects and deliver antibiotics locally for a long period. In this study, CPC was composited with the millimeter-sized spherical beads of cross-linked gelatin–alginate hydrogels at the different ratios of 0 (control), 12.5, 25, and 50 vol.%. The hydrogel was impregnated with gentamicin and characterized before compositing with CPC. The physicochemical properties, gentamicin release, antibacterial activity, biocompatibility, and mineralization of the CPC/hydrogel composites were characterized. The compressive strength of the CPC/hydrogel composites gradually decreased as the hydrogel content increased, and the compressive strength of composites containing gentamicin had the largest decrease. The working time and setting time of each group can be adjusted to 8 and 16 min, respectively, using a hardening solution to make the composite suitable for clinical use. The release of gentamicin before the hydrogel beads was composited with CPC varied greatly with immersion time. However, a stable controlled release effect was obtained in the CPC/gentamicin-impregnated hydrogel composite. The 50 vol.% hydrogel/CPC composite had the best antibacterial effect and no cytotoxicity but had reduced cell mineralization. Therefore, the optimal hydrogel beads content can be 25 vol.% to obtain a CPC/gentamicin-impregnated hydrogel composite with adequate strength, antibacterial activity, and bio-reactivity. This CPC/hydrogel containing gentamicin is expected to be used in clinical surgery in the future to accelerate bone regeneration and prevent prosthesis infection after surgery.
19
Melek Tezcan, Melek Tezcan, Huseyin Cicek Huseyin Cicek und Meryem Cicek and Said Nadeem Meryem Cicek and Said Nadeem. „Tuning Photocatalytic Activity and Decomposition Properties of Poly(Polyethylene Glycol Diacrylate-co-Hydroxyethyl Methacrylate)/TiO2 Composite Hydrogel“. Journal of the chemical society of pakistan 41, Nr. 4 (2019): 598. http://dx.doi.org/10.52568/000778/jcsp/41.04.2019.
Der volle Inhalt der QuelleAnnotation:
We have synthesized TiO2-loaded porous polyethylene glycol diacrylate-co-hydroxyethyl methacrylate (poly(PEGDA-co-HEMA)) hydrogel composites having tunable photocatalytic properties with structural decomposition. TiO2 was loaded over hydrogels by impregnation of titanium oxobutyrate (Ti(OBu)4), peptized at room temperature that resulted poly(PEGDA-co-HEMA)/TiO2 composites. Pore morphology, crystalline structure and TiO2 content of the hydrogels/composites were examined using SEM, XRD and TGA analyses. Structural decomposition rate of the composite hydrogels and model contaminant (methyl orange) was performed under simulated sun light. Suitable pore size, morphology and higher PEGDA/HEMA ratio in the formulation increased the structural decomposition rate of the polymer that works as a TiO2 template. As the template breaks out, it leaves behind a porous TiO2 skeleton – thus accelerates the photocatalytic activity. Although the TiO2 template did not formed at lower PEGDA/HEMA ratio and lower molecular weight of PEGDA, decomposition rate of the composite slowed down (10 % in 108 h). The prepared hydrogels can be used in the skin care andamp; engineering and waste water treatments.
20
Timofejeva, Anna, und Dagnija Loca. „Hydroxyapatite/Polyvinyl Alcohol Composite Hydrogels for Bone and Cartilage Tissue Engineering“. Key Engineering Materials 762 (Februar 2018): 54–58. http://dx.doi.org/10.4028/www.scientific.net/kem.762.54.
Der volle Inhalt der QuelleAnnotation:
Composite hydrogels on the basis of hydroxyapatite (HAp) and polyvinyl alcohol (PVA) has been proposed as a promising materials for bone and cartilage tissue engineering. HAp/PVA composite hydrogels with phase ratio 50:50wt% and 70:30wt% were obtained via in situ wet chemical precipitation technique in combination with the freeze-thawing approach. The XRD studies of sintered products revealed that HAp/PVA composite hydrogels synthesized from PVA with degree of hydrolysis (DH) 98% and molecular weights (MW) 25 kDa and 78 kDa are more suitable for biomedical purposes due to the formation of stoichiometric HAp. Swelling studies indicated that HAp/PVA 50:50 (78 kDa, 88% and 98%) hydrogels after 24h of immersion swell ~4.25-6.5 times less than identical samples with phase composition of 70:30wt%, which is accounted to different number of intermolecular hydrogen bonds formed. After 16 subsequent freeze-thawing cycles (FTC), HAp/PVA 50:50 (78 kDa, 88% and 98%) hydrogels contain ~1.2 times higher content of crosslinked PVA than HAp/PVA 70:30 (78 kDa, 88% and 98%) hydrogel samples.
21
Zhang, Jingjing, Qiuli Huang, Chungui Du, Rui Peng, Yating Hua, Qi Li, Ailian Hu und Junhui Zhou. „Preparation and Anti-Mold Properties of Nano-ZnO/Poly(N-isopropylacrylamide) Composite Hydrogels“. Molecules 25, Nr. 18 (10.09.2020): 4135. http://dx.doi.org/10.3390/molecules25184135.
Der volle Inhalt der QuelleAnnotation:
The aim of this study was to overcome drawbacks of the inhomogeneous dispersion and facile agglomeration of nano-ZnO/poly(N-isopropylacrylamide) composite hydrogels (nano-ZnO/PNIPAm composite hydrogels) during synthesis and improve the anti-mold property of the nano-ZnO/PNIPAm composite hydrogels. Here, nano-ZnO/PNIPAm composite hydrogels were prepared by the radical polymerization method. Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM), differential scanning calorimeter (DSC), and dynamic light scattering (DLS) were used to characterize the effects of different dispersants on the particle sizes, dispersions, and phase transition characteristics of the nano-ZnO/PNIPAm composite hydrogels. The anti-mold properties of nano-ZnO/PNIPAm composite hydrogels were studied. Results revealed that the nano-ZnO/PNIPAm composite hydrogel prepared by the addition of nano-ZnO dispersion liquid exhibited the smallest particle size, the most homogeneous dispersion, and the highest stability. The addition of the dispersant did not change the phase transition characteristics of nano-ZnO/PNIPAm, and the nano-ZnO/PNIPAm composite hydrogels (Pf) exhibited good anti-mold properties to the bamboo mold.
22
Chuah, Clarence, Jing Wang, Javad Tavakoli und Youhong Tang. „Novel Bacterial Cellulose-Poly (Acrylic Acid) Hybrid Hydrogels with Controllable Antimicrobial Ability as Dressings for Chronic Wounds“. Polymers 10, Nr. 12 (29.11.2018): 1323. http://dx.doi.org/10.3390/polym10121323.
Der volle Inhalt der QuelleAnnotation:
This investigation examines the combination of poly (acrylic acid) (PAA) and bacterial cellulose (BC) nanofibers to synthesize hydrogel hybrid composites used for wound dressing application. Amoxicillin (AM) was also grafted onto the composites for drug release. Fourier transform infrared analysis and scanning electron microscopy conducted revealed the structure and porosity of the composite being developed, as well as the successful fabrication of BC-PAA composites. The results of mechanical testing and hygroscopicity revealed that the composite shows higher stability than hydrogels which are currently used worldwide, albeit with a slight reduction in swelling capabilities. However, the composite was revealed to be responsive to a rise in pH values with an increase in composite swelling and drug release. These results together with their morphological characteristics suggest that BC-PAA hydrogel hybrid composite is a promising candidate for wound dressing application.
23
Zhang, Yingpu, Rong Huang, Si Peng und Zhaocheng Ma. „MWCNTs/Cellulose Hydrogels Prepared from NaOH/Urea Aqueous Solution with Improved Mechanical Properties“. Journal of Chemistry 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/413497.
Der volle Inhalt der QuelleAnnotation:
Novel high strength composite hydrogels were designed and synthesized by introducing multiwalled carbon nanotubes (MWCNTs) into cellulose/NaOH/urea aqueous solution and then cross-linked by epichlorohydrin. MWCNTs were used to modify the matrix of cellulose. The structure and morphology of the hydrogels were characterized by Fourier transform infrared (FT-IR) spectroscopy, high resolution transmission electron microscopy (HR-TEM), and scanning electron microscopy (SEM). The results from swelling testing revealed that the equilibrium swelling ratio of hydrogels decreased with the increment of MWCNTs content. Thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA) results demonstrated that the introduction of MWCNT into cellulose hydrogel networks remarkably improved both thermal and mechanical properties of the composite hydrogels. The preparation of MWCNTs modifiedcellulose-based composites with improved mechanical properties was the first important step towards the development of advanced functional materials.
24
GÜZEL KAYA, Gülcihan, und Hüseyin DEVECİ. „Characterization of Stimuli-Responsive Acrylamide/Sodium Methacrylate/Kaolin Semi-Interpenetrating Polymer Network Composite Hydrogels“. Afyon Kocatepe University Journal of Sciences and Engineering 23, Nr. 4 (29.08.2023): 984–90. http://dx.doi.org/10.35414/akufemubid.1247090.
Der volle Inhalt der QuelleAnnotation:
With the advantages of their self-healing, stimuli-response ability, water sorption capacity and shape memory, hydrogels have been commonly utilized. However, new strategies have been developed to enhance mechanical and thermal properties of hydrogels in addition to increase their water sorption. In this study, stimuli-responsive acrylamide/sodium methacrylate based hydrogels were synthesized with the optimization of sodium methacrylate amount by free radical polymerization. With the incorporation of optimum amount of polyethylene glycol 400 (PEG-400) into the hydrogel network, semi-interpenetrating polymer network (semi-IPN) hydrogels were prepared. With the addition of kaolin, swelling properties of the semi-IPN composite hydrogels were investigated in water under the effect of different pH and temperature. Maximum swelling percent of the semi-IPN composite hydrogels was determined as 24214% at pH 7 and 25 °C. Fourier transform infrared spectroscopy (FTIR) analyses revealed that hydrogel samples were successfully synthesized. Morphological structure of hydrogel samples was examined by scanning electron microscopy (SEM) analyses. Both of the water motion through the hydrogel layered structure and water diffusion into the pores made the semi-IPN composite hydrogel more swollen material compared to the acrylamide/sodium methacrylate based hydrogel.
25
Hasan, Md Mahmudul, Md Forhad Uddin, Nayera Zabin, Md Salman Shakil, Morshed Alam, Fahima Jahan Achal, Most Hosney Ara Begum, Md Sakib Hossen, Md Ashraful Hasan und Md Mahbubul Morshed. „Fabrication and Characterization of Chitosan-Polyethylene Glycol (Ch-Peg) Based Hydrogels and Evaluation of Their Potency in Rat Skin Wound Model“. International Journal of Biomaterials 2021 (14.10.2021): 1–11. http://dx.doi.org/10.1155/2021/4877344.
Der volle Inhalt der QuelleAnnotation:
Thermal burns are a major cause of death and suffering around the globe. They can cause debilitating, life-altering injuries as well as lead to significant psychological and financial consequences. Several research works have been conducted in attempt to find a wound healing therapy that is successful. At present, hydrogels have been widely used in cutting-edge research for this purpose because they have suitable properties. This study aimed to see how therapy with chitosan-polyethylene glycol (Ch-Peg) based hydrogels affected the healing of burn wounds in rats. With the concern of public health, xanthan gum (X), boric acid (B), gelatin (Ge), polyethylene glycol (Peg), chitosan (Ch), glutaraldehyde (G), and HPLC-grade water were prepared using X : Ge : G, X : Ge : Peg : G, X : Ge : Ch : G, X : Ge : Peg : Ch : G, X : Ge : B : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch : G. The produced composite hydrogels were examined for swelling ability, biodegradability, rheological characteristics, and porosity. The 3D structure of the hydrogel was revealed by scanning electron microscopy (SEM). After that, the structural characterization technique named Fourier-transform infrared spectroscopy (FTIR) was used to describe the composites (SEM). Lastly, in a rat skin wound model, the efficacy of the produced hydrogels was studied. Swelling ability, biodegradability, rheological properties, and porosity were all demonstrated in composite hydrogels that contained over 90% water. Hydrogels with good polymeric networks and porosity were observed using SEM. The existence of bound water and free, intra- and intermolecule hydrogen-linked OH and NH in the hydrogels was confirmed using FTIR. In a secondary burned rat model, all hydrogels showed significant wound healing effectiveness when compared to controls. When compared to other composite hydrogels, wounds treated with X : Ge : Peg : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch:G recovered faster after 28 days. In conclusion, this research suggests that X : Ge : Peg : Ch : G, X : Ge : B : Peg : G, and X : Ge : B : Peg : Ch : G could be used to treat skin injuries in the clinic.
26
Ambrosio, L., R. De Santis und L. Nicolais. „Composite hydrogels for implants“. Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 212, Nr. 2 (01.02.1998): 93–99. http://dx.doi.org/10.1243/0954411981533863.
Der volle Inhalt der QuelleAnnotation:
Hydrophilic composite structures are designed to mimic the transport and mechanical properties of natural soft tissue such as tendons, ligaments and intervertebral discs. Mechanical and viscoelastic behaviour of a soft composite material based on a hydrogel matrix reinforced with bundles of polyethylene therephthalate (PET) fibres is analysed. The typical J-shaped stress-strain behaviour, displayed by natural tendons and ligaments, is reproduced. The mechanical characteristics, such as the extent of the ‘toe-in region’ and the elastic modulus in the linear region, can be controlled by varying the winding angle of the fibres and the matrix composition. Dynamic mechanical analysis showed the dual behaviour of the composite systems due to the progressive contribution of the PET fibres. Different poly (2-hydroxyethylmethacrylate)/polycaprolactone (PHEMA/PCL) semi-interpenetrating polymer networks (IPNs) hydrogel composite systems reinforced with PET fibres have been investigated for potential use as intervertebral disc prostheses. Compression properties have been evaluated by static and dynamic tests. Uniaxial compression tests on the swollen samples showed an increase of the modulus and maximum stress with increasing content of PCL and PET fibres. Creep behaviour is also dependent on the hydrogel composition. The composite PHEMA/PCL hydrogels showed compression properties similar to those expressed by canine intervertebral discs in different spinal locations.
27
Chen, Chengfeng, Yimiao Wang, Hang Wang, Xinqing Wang und Mingwei Tian. „Electronic Skin Based on Polydopamine-Modified Superelastic Fibers with Superior Conductivity and Durability“. Nanomaterials 14, Nr. 5 (28.02.2024): 438. http://dx.doi.org/10.3390/nano14050438.
Der volle Inhalt der QuelleAnnotation:
Owing to their excellent elasticities and adaptability as sensing materials, ionic hydrogels exhibit significant promise in the field of intelligent wearable devices. Nonetheless, molecular chains within the polymer network of hydrogels are susceptible to damage, leading to crack extension. Hence, we drew inspiration from the composite structure of the human dermis to engineer a composite hydrogel, incorporating dopamine-modified elastic fibers as a reinforcement. This approach mitigates crack expansion and augments sensor sensitivity by fostering intermolecular forces between the dopamine on the fibers, the hydrogel backbone, and water molecules. The design of this composite hydrogel elevates its breaking tensile capacity from 35 KJ to 203 KJ, significantly enhancing the fatigue resistance of the hydrogel. Remarkably, its electrical properties endure stability even after 2000 cycles of testing, and it manifests heightened sensitivity compared to conventional hydrogel configurations. This investigation unveils a novel method for crafting composite-structured hydrogels.
28
Kocak, Fatma Z., Muhammad Yar und Ihtesham U. Rehman. „Hydroxyapatite-Integrated, Heparin- and Glycerol-Functionalized Chitosan-Based Injectable Hydrogels with Improved Mechanical and Proangiogenic Performance“. International Journal of Molecular Sciences 23, Nr. 10 (11.05.2022): 5370. http://dx.doi.org/10.3390/ijms23105370.
Der volle Inhalt der QuelleAnnotation:
The investigation of natural bioactive injectable composites to induce angiogenesis during bone regeneration has been a part of recent minimally invasive regenerative medicine strategies. Our previous study involved the development of in situ-forming injectable composite hydrogels (Chitosan/Hydroxyapatite/Heparin) for bone regeneration. These hydrogels offered facile rheology, injectability, and gelation at 37 °C, as well as promising pro-angiogenic abilities. In the current study, these hydrogels were modified using glycerol as an additive and a pre-sterile production strategy to enhance their mechanical strength. These modifications allowed a further pH increment during neutralisation with maintained solution homogeneity. The synergetic effect of the pH increment and further hydrogen bonding due to the added glycerol improved the strength of the hydrogels substantially. SEM analyses showed highly cross-linked hydrogels (from high-pH solutions) with a hierarchical interlocking pore morphology. Hydrogel solutions showed more elastic flow properties and incipient gelation times decreased to just 2 to 3 min at 37 °C. Toluidine blue assay and SEM analyses showed that heparin formed a coating at the top layer of the hydrogels which contributed anionic bioactive surface features. The chick chorioallantoic membrane (CAM) assay confirmed significant enhancement of angiogenesis with chitosan-matrixed hydrogels comprising hydroxyapatite and small quantities of heparin (33 µg/mL) compared to basic chitosan hydrogels.
29
Sakai, Shinji, Hiromi Ohi und Masahito Taya. „Gelatin/Hyaluronic Acid Content in Hydrogels Obtained through Blue Light-Induced Gelation Affects Hydrogel Properties and Adipose Stem Cell Behaviors“. Biomolecules 9, Nr. 8 (05.08.2019): 342. http://dx.doi.org/10.3390/biom9080342.
Der volle Inhalt der QuelleAnnotation:
Composite hydrogels of hyaluronic acid and gelatin attract great attention in biomedical fields. In particular, the composite hydrogels obtained through processes that are mild for cells are useful in tissue engineering. In this study, hyaluronic acid/gelatin composite hydrogels obtained through a blue light-induced gelation that is mild for mammalian cells were studied for the effect of the content of each polymer in the precursor solution on gelation, properties of resultant hydrogels, and behaviors of human adipose stem cells laden in the hydrogels. Control of the content enabled gelation in less than 20 s, and also enabled hydrogels to be obtained with 0.5–1.2 kPa Young’s modulus. Human adipose stem cells were more elongated in hydrogels with a higher rather than lower content of hyaluronic acid. Stem cell marker genes, Nanog, Oct4, and Sox2, were expressed more in the cells in the composite hydrogels with a higher content of hyaluronic acid compared with those in the hydrogel composed of gelatin alone and on tissue culture dishes. These results are useful for designing conditions for using gelatin/hyaluronic acid composite hydrogels obtained through blue light-induced gelation suitable for tissue engineering applications.
30
Zhang, Junyu, und Zhao Wang. „Nanoparticle–Hydrogel Based Sensors: Synthesis and Applications“. Catalysts 12, Nr. 10 (22.09.2022): 1096. http://dx.doi.org/10.3390/catal12101096.
Der volle Inhalt der QuelleAnnotation:
Hydrogels are hydrophilic three-dimensional (3D) porous polymer networks that can easily stabilize various nanoparticles. Loading noble metal nanoparticles into a 3D network of hydrogels can enhance the synergy of the components. It can also be modified to prepare intelligent materials that can recognize external stimuli. The combination of noble metal nanoparticles and hydrogels to produce modified or new composite materials has attracted considerable attention as to the use of these materials in sensors. However, there is limited review literature on nanoparticle–hydrogel-based sensors. This paper presents the detailed strategies of synthesis and design of the composites, and the latest applications of nanoparticle–hydrogel materials in the sensing field. Finally, the current challenges and future development directions of nanoparticle–hydrogel-based sensors are proposed.
31
Simeonov, Marin, Anton Atanasov Apostolov, Milena Georgieva, Dimitar Tzankov und Elena Vassileva. „Poly(acrylic acid-co-acrylamide)/Polyacrylamide pIPNs/Magnetite Composite Hydrogels: Synthesis and Characterization“. Gels 9, Nr. 5 (26.04.2023): 365. http://dx.doi.org/10.3390/gels9050365.
Der volle Inhalt der QuelleAnnotation:
Novel composite hydrogels based on poly(acrylic acid-co-acrylamide)/polyacrylamide pseudo-interpenetrating polymer networks (pIPNs) and magnetite were prepared via in situ precipitation of Fe3+/Fe2+ ions within the hydrogel structure. The magnetite formation was confirmed by X-ray diffraction, and the size of the magnetite crystallites was shown to depend on the hydrogel composition: the crystallinity of the magnetite particles increased in line with PAAM content within the composition of the pIPNs. The Fourier transform infrared spectroscopy revealed an interaction between the hydrogel matrix, via the carboxylic groups of polyacrylic acid, and Fe ions, which strongly influenced the formation of the magnetite articles. The composites’ thermal properties, examined using differential scanning calorimetry (DSC), show an increase in the glass transition temperature of the obtained composites, which depends on the PAA/PAAM copolymer ratio in the pIPNs’ composition. Moreover, the composite hydrogels exhibit pH and ionic strength responsiveness as well as superparamagnetic properties. The study revealed the potential of pIPNs as matrices for controlled inorganic particle deposition as a viable method for the production of polymer nanocomposites.
32
Takeno, Hiroyuki, Rina Shikano und Rin Kikuchi. „Mechanical Performance of Corn Starch/Poly(Vinyl Alcohol) Composite Hydrogels Reinforced by Inorganic Nanoparticles and Cellulose Nanofibers“. Gels 8, Nr. 8 (18.08.2022): 514. http://dx.doi.org/10.3390/gels8080514.
Der volle Inhalt der QuelleAnnotation:
We investigated the mechanical properties of corn starch (CS)/poly(vinyl alcohol) (PVA)/borax hydrogels reinforced by clay platelets, silica (SiO2) nanospheres, or cellulose nanofibers (CNFs). The effects of these reinforcing agents on the tensile properties of the hydrogels were quite different; the fracture stress of SiO2/CS/PVA/borax composite hydrogels increased with SiO2 concentration, whereas that of clay/CS/PVA/borax composite hydrogels was high at a low clay concentration but low at high clay concentrations; for CNF/CS/PVA/borax composite hydrogels, although the elastic modulus was highly enhanced by adding CNF, the fracture stress was very low because of the stress relaxation during the elongation. This result came from differences in the dispersibility of each filler and the reinforcing ability. These composite hydrogels were constructed by multi-crosslinking, such as hydrogen bonding between CS and PVA, CS and PVA crystals, complexation between borate and PVA (partly CS), and the crosslinking between each filler and polymer. The self-healing ability of SiO2 and clay composite hydrogels was examined. As a result, the SiO2/CS/PVA/borax composite hydrogels possessed an excellent self-healing ability, whereas the clay/CS/PVA/borax composite hydrogels had a poor self-healing ability.
33
Cuéllar Gaona, Claudia Gabriela, María Cristina Ibarra Alonso, Rosa Idalia Narro Céspedes, María Maura Téllez Rosas, Ricardo Reyna Martínez und Miriam Paulina Luévanos Escareño. „Novel Studies in the Designs of Natural, Synthetic, and Compound Hydrogels with Biomedical Applications“. Revista Mexicana de Ingeniería Biomédica 44, Nr. 2 (01.05.2023): 74–96. http://dx.doi.org/10.17488/rmib.44.2.6.
Der volle Inhalt der QuelleAnnotation:
Hydrogels are gaining widespread popularity in the biomedical field due to their extraordinary properties, such as biocompatibility, biodegradability, zero toxicity, easy processing, and similarity to physiological tissue. They have applications in controlled drug release, wound dressing, tissue engineering, and regenerative medicine. Among these applications, hydrogels as a controlled drug delivery system stands out, which releases active substances in precise amounts and at specific times. To explore the latest advances in the design of hydrogels, a literature review of articles published in indexed scientific journals, in Scopus and Science Direct, was carried out. This review aimed to discover and describe the most innovative hydrogel research with applications in the biomedical field; hydrogels synthesized with polymers of different origins were selected, such as; i. Natural (dextran, agarose, chitosan, etc.); ii. Synthetic (polyacrylamide, polyethylene glycol, polyvinyl alcohol, etc.); iii. Composites (interpenetrants, hybrid crosslinkers, nanocomposites, etc.). Comparative analysis revealed that hydrogels with composite materials show the most promise. These composite hydrogels combine the advantages of different polymers or incorporate additional components, offering enhanced properties and functionalities. In summary, hydrogels are versatile biomaterials with immense potential in biomedicine. Their unique properties make them suitable for diverse applications. However, innovative designs and formulations must continue to be explored to further advance the capabilities of hydrogels and expand their biomedical applications.
34
Xiang, Changxin, Xinyan Zhang, Jianan Zhang, Weiyi Chen, Xiaona Li, Xiaochun Wei und Pengcui Li. „A Porous Hydrogel with High Mechanical Strength and Biocompatibility for Bone Tissue Engineering“. Journal of Functional Biomaterials 13, Nr. 3 (03.09.2022): 140. http://dx.doi.org/10.3390/jfb13030140.
Der volle Inhalt der QuelleAnnotation:
Polyvinyl alcohol (PVA) hydrogels are considered to be ideal materials for tissue engineering due to their high water content, low frictional behavior, and good biocompatibility. However, their limited mechanical properties restrict them from being applied when repairing load-bearing tissue. Inspired by the composition of mussels, we fabricated polyvinyl alcohol/hydroxyapatite/tannic acid (PVA/HA/TA) hydrogels through a facile freeze–thawing method. The resulting composite hydrogels exhibited high moisture content, porous structures, and good mechanical properties. The compressive strength and tensile strength of PVA hydrogels were improved from 0.77 ± 0.11 MPa and 0.08 ± 0.01 MPa to approximately 3.69 ± 0.41 MPa and 0.43 ± 0.01 MPa, respectively, for the PVA/HA/1.5TA hydrogel. The toughness and the compressive elastic modulus of PVA/HA/1.5TA hydrogel also attained 0.86 ± 0.02 MJm−3 and 0.11 ± 0.02 MPa, which was approximately 11 times and 5 times higher than the PVA hydrogel, respectively. The PVA/HA/1.5TA hydrogel also exhibited fatigue resistance abilities. The mechanical properties of the composite hydrogels were improved through the introduction of TA. Furthermore, in vitro PVA/HA/1.5TA hydrogel showed excellent cytocompatibility by promoting cell proliferation in vitro. Scanning electron microscopy analysis indicated that PVA/HA/1.5TA hydrogels provided favorable circumstances for cell adhesion. The aforementioned results also indicate that the composite hydrogels had potential applications in bone tissue engineering, and this study provides a facile method to improve the mechanical properties of PVA hydrogel.
35
Shang, Jiaojiao, und Patrick Theato. „Smart composite hydrogel with pH-, ionic strength- and temperature-induced actuation“. Soft Matter 14, Nr. 41 (2018): 8401–7. http://dx.doi.org/10.1039/c8sm01728j.
Der volle Inhalt der QuelleAnnotation:
A facile and versatile photo-patterning method to fabricate “smart” hydrogels with defined lateral and vertical inhomogeneity of hydrogel composition and dimensions has been developed via generating programmable composite hydrogels and bilayer hydrogels based on thermal and ionic strength-responsive poly(N-isopropylacrylamide) and pH-sensitive poly(acrylic acid) hydrogels.
36
Lee, Jeong Yun, Hyun Ho Shin, Chungyeon Cho und Ji Hyun Ryu. „Effect of Tannic Acid Concentrations on Temperature-Sensitive Sol–Gel Transition and Stability of Tannic Acid/Pluronic F127 Composite Hydrogels“. Gels 10, Nr. 4 (10.04.2024): 256. http://dx.doi.org/10.3390/gels10040256.
Der volle Inhalt der QuelleAnnotation:
Recently, interest in polyphenol-containing composite adhesives for various biomedical applications has been growing. Tannic acid (TA) is a polyphenolic compound with advantageous properties, including antioxidant and antimicrobial properties. Additionally, TA contains multiple hydroxyl groups that exhibit biological activity by forming hydrogen bonds with proteins and biomacromolecules. Furthermore, TA-containing polymer composites exhibit excellent tissue adhesion properties. In this study, the gelation behavior and adhesion forces of TA/Pluronic F127 (TA/PluF) composite hydrogels were investigated by varying the TA and PluF concentrations. PluF (above 16 wt%) alone showed temperature-responsive gelation behavior because of the closely packed micelle aggregates. After the addition of a small amount of TA, the TA/PluF hydrogels showed thermosensitive behavior similar to that of PluF hydrogels. However, the TA/PluF hydrogels containing more than 10 wt% TA completely suppressed the thermo-responsive gelation kinetics of PluF, which may have been due to the hydrogen bonds between TA and PluF. In addition, TA/PluF hydrogels with 40 wt% TA showed excellent tissue adhesion properties and bursting pressure in porcine intestinal tissues. These results are expected to aid in understanding the use of mixtures of TA and thermosensitive block copolymers to fabricate adhesive hydrogels for versatile biomedical applications.
37
Malekmohammadi, Samira, Negar Sedghi Aminabad, Amin Sabzi, Amir Zarebkohan, Mehdi Razavi, Massoud Vosough, Mahdi Bodaghi und Hajar Maleki. „Smart and Biomimetic 3D and 4D Printed Composite Hydrogels: Opportunities for Different Biomedical Applications“. Biomedicines 9, Nr. 11 (26.10.2021): 1537. http://dx.doi.org/10.3390/biomedicines9111537.
Der volle Inhalt der QuelleAnnotation:
In recent years, smart/stimuli-responsive hydrogels have drawn tremendous attention for their varied applications, mainly in the biomedical field. These hydrogels are derived from different natural and synthetic polymers but are also composite with various organic and nano-organic fillers. The basic functions of smart hydrogels rely on their ability to change behavior; functions include mechanical, swelling, shaping, hydrophilicity, and bioactivity in response to external stimuli such as temperature, pH, magnetic field, electromagnetic radiation, and biological molecules. Depending on the final applications, smart hydrogels can be processed in different geometries and modalities to meet the complicated situations in biological media, namely, injectable hydrogels (following the sol-gel transition), colloidal nano and microgels, and three dimensional (3D) printed gel constructs. In recent decades smart hydrogels have opened a new horizon for scientists to fabricate biomimetic customized biomaterials for tissue engineering, cancer therapy, wound dressing, soft robotic actuators, and controlled release of bioactive substances/drugs. Remarkably, 4D bioprinting, a newly emerged technology/concept, aims to rationally design 3D patterned biological matrices from synthesized hydrogel-based inks with the ability to change structure under stimuli. This technology has enlarged the applicability of engineered smart hydrogels and hydrogel composites in biomedical fields. This paper aims to review stimuli-responsive hydrogels according to the kinds of external changes and t recent applications in biomedical and 4D bioprinting.
38
Thinh, Nguyen Tien. „ENZYMATIC PREPARATION OF MODULATED–BIODEGRADABLE HYDROGEL NANOCOMPOSITES BASED CHITOSAN/GELATIN AND BIPHASIC CALCIUM PHOSPHATE NANOPARTICLES“. Vietnam Journal of Science and Technology 55, Nr. 1B (23.03.2018): 185. http://dx.doi.org/10.15625/2525-2518/55/1b/12107.
Der volle Inhalt der QuelleAnnotation:
In the study, injectable chitosan–4 hydroxyphenylacectamide acid (CHPA) and gelatin–tyramine (GTA)–based hydrogels were enzymatically prepared, in which could encapsulate biphasic calcium phosphate nanoparticles (BCP NPs) for enhancing bone regeneration. The in situ formation of hydrogel composite was varied from 35 to 80 seconds depending on concentration of H2O2. Collagenase–mediated biodegradation of the hydrogel composite could be modulated from 3 days to over one month depending on amount of the formulated CHPA. Live/dead cell viability assay indicated that the hydrogel composite enhanced bone marrow mesenchymal stem cells (MSCs). The obtained results show a great potential of the hydrogel composites for bone regeneration due to its adjustable biodegradation, biocompatibility and enhancement in new bone formation.
39
Cheng, Heli, Xu Zhang, Jiawei Xu und Sicheng Liu. „Preparation of xanthan gum-based composite hydrogels with aligned porous structure“. BioResources 15, Nr. 3 (29.05.2020): 5627–40. http://dx.doi.org/10.15376/biores.15.3.5627-5640.
Der volle Inhalt der QuelleAnnotation:
Aligned hydrogels have received increasing attention in tissue engineering and electrochemical fields due to their favorable structure. In this work, xanthan gum-based hydrogels (XGH) with aligned pores were prepared via photoinitiated free radical irradiation that used sodium acetate crystals as template. The microstructure, compressive strength, porosity, and absorption capacity of the hydrogel were studied and compared with the non-aligned hydrogels. Scanning electron microscope analysis confirmed the aligned porous structure of the hydrogel. The maximum compressive strength for the aligned hydrogel prepared with 12% acrylamide and 1.5% xanthan gum reached 0.439 MPa at a strain of 95%. Furthermore, aligned XGH exhibited better flexibility than non-aligned hydrogels, as indicated by the Young’s compressive modulus. The porosity of the aligned hydrogels ranged from 94.9% to 88.8% as the acrylamide concentration increased from 12% to 20%. Simulated body fluid absorption showed that hydrogels with aligned pores could attain absorption equilibrium within 5 min, and the maximum absorption capacity reached 33.6 g/g for the sample made with 0.5% xanthan gum and 12% acrylamide. In addition, exhibited preferable biocompatibility, as demonstrated by the cytotoxicity test.
40
Suresh, Selvaraj, S. Ravichandran, Ishan Y. Pandya, S. S. Sreeja Mole, S. R. Boselin Prabhu und G. K. Prashanth. „Alginate Hydrogel Adsorbents in Adsorption of Inorganic and Organic Pollutants: A Review“. Asian Journal of Chemistry 34, Nr. 7 (2022): 1625–32. http://dx.doi.org/10.14233/ajchem.2022.23712.
Der volle Inhalt der QuelleAnnotation:
The present review discusses various alginate hydrogel adsorbents with unique adsorption performance in environmental remediation. Novel alginate composites were developed with, high swelling capacity and capable of adsorbing toxic inorganic and organic pollutants. Alginate hydrogel adsorbents were developed with a single network and double network structure with excellent adsorption ability in removal of toxic inorganic and/or organic pollutants. Alginate with single or double network composite hydrogels were developed when alginate was combined with graphene/chitosan/polymer to get superior adsorbents in removal of toxic pollutants. Acrylic acid/alginate hydrogel in recent studies are efficient in the elimination of inorganic and organic contaminants. This review will generate interest to researchers to develop novel alginate composite hydrogels with unique properties in the adsorption of toxic inorganic, organic contaminants. This work provides a worthy challenge and the future possibility of designing novel alginate materials for various applications.
41
Sokolov, Pavel, Pavel Samokhvalov, Alyona Sukhanova und Igor Nabiev. „Biosensors Based on Inorganic Composite Fluorescent Hydrogels“. Nanomaterials 13, Nr. 11 (26.05.2023): 1748. http://dx.doi.org/10.3390/nano13111748.
Der volle Inhalt der QuelleAnnotation:
Fluorescent hydrogels are promising candidate materials for portable biosensors to be used in point-of-care diagnosis because (1) they have a greater capacity for binding organic molecules than immunochromatographic test systems, determined by the immobilization of affinity labels within the three-dimensional hydrogel structure; (2) fluorescent detection is more sensitive than the colorimetric detection of gold nanoparticles or stained latex microparticles; (3) the properties of the gel matrix can be finely tuned for better compatibility and detection of different analytes; and (4) hydrogel biosensors can be made to be reusable and suitable for studying dynamic processes in real time. Water-soluble fluorescent nanocrystals are widely used for in vitro and in vivo biological imaging due to their unique optical properties, and hydrogels based on these allow the preservation of these properties in bulk composite macrostructures. Here we review the techniques for obtaining analyte-sensitive fluorescent hydrogels based on nanocrystals, the main methods used for detecting the fluorescent signal changes, and the approaches to the formation of inorganic fluorescent hydrogels via sol–gel phase transition using surface ligands of the nanocrystals.
42
Srirachya, Nuttida, Kanoktip Boonkerd und Takaomi Kobayashi. „Effective elongation properties of cellulose–natural rubber composite hydrogels having interconnected domain“. Journal of Elastomers & Plastics 52, Nr. 4 (21.05.2019): 337–55. http://dx.doi.org/10.1177/0095244319849699.
Der volle Inhalt der QuelleAnnotation:
This report describes progress in the development of cellulose hydrogel by blending with natural rubber (NR). Cellulose regenerated from the bagasse sugarcane was used for this study. Although cellulose and NR have a considerably low mutual affinity, composite hydrogels with various cellulose and NR contents were prepared using a wet-phase inversion method. The maximum amount of NR that can be loaded into the cellulose hydrogel was about 30% vol. Once NR is introduced into the cellulose hydrogels, the obtained hydrogel became translucent and eventually opaque with increasing NR loading. Measurements of water absorption, the water contact angle, and evaluation of fourier-transform infrared spectroscopoy (FTIR) spectra revealed that the presence of NR decreases the water affinity of the hydrogels. Nevertheless, it is noteworthy that the composite hydrogels had higher tensile strength and better elastic properties than the pristine hydrogel. The results showed that the obtained composite hydrogels can be elongated several times to their original length. The enhancement of both properties was proportional to the amount of NR included. Results of scanning electron microscope (SEM) images showed NR present inside the hollow of the cellulose hydrogel, forming interconnected domains. One can infer that the increase of mechanical and elastic properties is attributable to the presence of these interconnected structures.
43
Fu, Fanfan, Zhuoyue Chen, Ze Zhao, Huan Wang, Luoran Shang, Zhongze Gu und Yuanjin Zhao. „Bio-inspired self-healing structural color hydrogel“. Proceedings of the National Academy of Sciences 114, Nr. 23 (22.05.2017): 5900–5905. http://dx.doi.org/10.1073/pnas.1703616114.
Der volle Inhalt der QuelleAnnotation:
Biologically inspired self-healing structural color hydrogels were developed by adding a glucose oxidase (GOX)- and catalase (CAT)-filled glutaraldehyde cross-linked BSA hydrogel into methacrylated gelatin (GelMA) inverse opal scaffolds. The composite hydrogel materials with the polymerized GelMA scaffold could maintain the stability of an inverse opal structure and its resultant structural colors, whereas the protein hydrogel filler could impart self-healing capability through the reversible covalent attachment of glutaraldehyde to lysine residues of BSA and enzyme additives. A series of unprecedented structural color materials could be created by assembling and healing the elements of the composite hydrogel. In addition, as both the GelMA and the protein hydrogels were derived from organisms, the composite materials presented high biocompatibility and plasticity. These features of self-healing structural color hydrogels make them excellent functional materials for different applications.
44
Zhao, Benbo, Mingda Zhao, Liming Li, Shixiong Sun, Heping Yu, Yuan Cheng, Yuedi Yang, Yujiang Fan und Yong Sun. „Preparation and Properties of Double-Crosslinked Hydroxyapatite Composite Hydrogels“. International Journal of Molecular Sciences 23, Nr. 17 (01.09.2022): 9962. http://dx.doi.org/10.3390/ijms23179962.
Der volle Inhalt der QuelleAnnotation:
Natural polymer hydrogels have good mechanical properties and biocompatibility. This study designed hydroxyapatite-enhanced photo-oxidized double-crosslinked hydrogels. Hyaluronic acid (HA) and gelatin (Gel) were modified with methacrylate anhydride. The catechin group was further introduced into the HA chain inspired by the adhesion chemistry of marine mussels. Hence, the double-crosslinked hydrogel (HG) was formed by the photo-crosslinking of double bonds and the oxidative-crosslinking of catechins. Moreover, hydroxyapatite was introduced into HG to form hydroxyapatite-enhanced hydrogels (HGH). The results indicate that, with an increase in crosslinking network density, the stiffness of hydrogels became higher; these hydrogels have more of a compact pore structure, their anti-degradation property is improved, and swelling property is reduced. The introduction of hydroxyapatite greatly improved the mechanical properties of hydrogels, but there is no change in the stability and crosslinking network structure of hydrogels. These inorganic phase-enhanced hydrogels were expected to be applied to tissue engineering scaffolds.
45
Jiang, Yuchen, Guihua Li, Chenyu Yang, Fangong Kong und Zaiwu Yuan. „Multiresponsive Cellulose Nanocrystal Cross-Linked Copolymer Hydrogels for the Controlled Release of Dyes and Drugs“. Polymers 13, Nr. 8 (09.04.2021): 1219. http://dx.doi.org/10.3390/polym13081219.
Der volle Inhalt der QuelleAnnotation:
Multiresponsive hydrogels have attracted tremendous interest due to their promising applications in tissue engineering, wearable devices, and flexible electronics. In this work, we report a multiresponsive upper critical solution temperature (UCST) composite hydrogel based on poly (acrylic acid-co-acrylamide), PAAc-co-PAAm, sequentially cross-linked by acid-hydrolysis cellulose nanocrystals (CNCs). Scanning electron microscopy (SEM) observations demonstrated that the hydrogels are formed by densely cross-linked porous structures. The PAAc/PAAm/CNC hybrid hydrogels exhibit swelling and shrinking properties that can be induced by multiple stimuli, including temperature, pH, and salt concentration. The driving force of the volume transition is the formation and dissociation of hydrogen bonds in the hydrogels. A certain content of CNCs can greatly enhance the shrinkage capability and mechanical strength of the hybrid hydrogels, but an excess addition may impair the contractility of the hydrogel. Furthermore, the hydrogels can be used as a matrix to adsorb dyes, such as methylene blue (MB), for water purification. MB may be partly discharged from hydrogels by saline solutions, especially by those with high ionic strength. Notably, through temperature-controlled hydrogel swelling and shrinking, doxorubicin hydrochloride (DOX-HCl) can be controllably adsorbed and released from the prepared hydrogels.
46
Patel, Madhumita, und Won-Gun Koh. „Composite Hydrogel of Methacrylated Hyaluronic Acid and Fragmented Polycaprolactone Nanofiber for Osteogenic Differentiation of Adipose-Derived Stem Cells“. Pharmaceutics 12, Nr. 9 (22.09.2020): 902. http://dx.doi.org/10.3390/pharmaceutics12090902.
Der volle Inhalt der QuelleAnnotation:
Composite hydrogels with electrospun nanofibers (NFs) have recently been used to mimic the native extracellular matrix. In this study, composite hydrogels of methacrylated hyaluronic acid containing fragmented polycaprolactone NFs were used for bone tissue engineering. The composite (NF/hydrogel) was crosslinked under ultraviolet (UV) light. The incorporation of fragmented polycaprolactone NFs increased the compression modulus from 1762.5 to 3122.5 Pa. Subsequently, adipose-derived stem cells incorporated into the composite hydrogel exhibited a more stretched and elongated morphology and osteogenic differentiation in the absence of external factors. The mRNA expressions of osteogenic biomarkers, including collagen 1 (Col1), alkaline phosphatase, and runt-related transcription factor 2, were 3–5-fold higher in the composite hydrogel than in the hydrogel alone. In addition, results of the protein expression of Col1 and alizarin red staining confirmed osteogenic differentiation. These findings suggest that our composite hydrogel provides a suitable microenvironment for bone tissue engineering.
47
Salahuddin, Bidita, Shazed Aziz, Shuai Gao, Md Shahriar A. Hossain, Motasim Billah, Zhonghua Zhu und Nasim Amiralian. „Magnetic Hydrogel Composite for Wastewater Treatment“. Polymers 14, Nr. 23 (22.11.2022): 5074. http://dx.doi.org/10.3390/polym14235074.
Der volle Inhalt der QuelleAnnotation:
Nanocomposite hydrogels are highly porous colloidal structures with a high adsorption capacity, making them promising materials for wastewater treatment. In particular, magnetic nanoparticle (MNP) incorporated hydrogels are an excellent adsorbent for aquatic pollutants. An added advantage is that, with the application of an external magnetic field, magnetic hydrogels can be collected back from the wastewater system. However, magnetic hydrogels are quite brittle and structurally unstable under compact conditions such as in fixed-bed adsorption columns. To address this issue, this study demonstrates a unique hydrogel composite bead structure, providing a good adsorption capacity and superior compressive stress tolerance due to the presence of hollow cores within the beads. The gel beads contain alginate polymer as the matrix and MNP-decorated cellulose nanofibres (CNF) as the reinforcing agent. The MNPs within the gel provide active adsorption functionality, while CNF provide a good stress transfer phenomenon when the beads are under compressive stress. Their adsorption performance is evaluated in a red mud solution for pollutant adsorption. Composite gel beads have shown high performance in adsorbing metal (aluminium, potassium, selenium, sodium, and vanadium) and non-metal (sulphur) contaminations. This novel hybrid hydrogel could be a promising alternative to the conventionally used toxic adsorbent, providing environmentally friendly operational benefits.
48
Yu, Jie, Fangli Ran, Chenyu Li, Zhenxin Hao, Haodong He, Lin Dai, Jingfeng Wang und Wenjuan Yang. „A Lignin Silver Nanoparticles/Polyvinyl Alcohol/Sodium Alginate Hybrid Hydrogel with Potent Mechanical Properties and Antibacterial Activity“. Gels 10, Nr. 4 (01.04.2024): 240. http://dx.doi.org/10.3390/gels10040240.
Der volle Inhalt der QuelleAnnotation:
Antibacterial hydrogels have attracted significant attention due to their diverse applications, efficient antimicrobial properties, and adaptability to various environments and requirements. However, their relatively fragile structure, coupled with the potential for environmental toxicity when exposed to their surroundings for extended periods, may significantly limit their practical application potential. In this work, a composite hydrogel was synthesized with outstanding mechanical features and antibacterial capability. The hydrogel was developed through the combination of the eco-friendly and enduring antibacterial agent, lignin silver nanoparticles (Lig-Ag NPs), with polyvinyl alcohol (PVA) and sodium alginate (SA), in varying proportions. The successful synthesis of the hydrogel and the dispersed distribution of Lig-Ag NPs within the hydrogel were confirmed by various analytical techniques, including field emission scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), mercury intrusion porosimetry (MIP), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The formation of multiple hydrogen bonds between Lig-Ag NPs and the composites contributed to a more stable and dense network structure of the hydrogel, consequently enhancing its mechanical properties. Rheological tests revealed that the hydrogel exhibited an elastic response and demonstrated outstanding self-recovery properties. Significantly, the antibacterial hydrogel demonstrated effectiveness against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), achieving a <5% survival of bacteria within 12 h. This study presented a green and straightforward synthetic strategy for the application of antibacterial composite hydrogels in various fields.
49
Sun, Ying, Duanxin Li, Yang Yu und Yongjie Zheng. „Insights into the Role of Natural Polysaccharide-Based Hydrogel Wound Dressings in Biomedical Applications“. Gels 8, Nr. 10 (12.10.2022): 646. http://dx.doi.org/10.3390/gels8100646.
Der volle Inhalt der QuelleAnnotation:
Acute skin damage caused by burns or cuts occurs frequently in people’s daily lives. Such wounds are difficult to heal normally and have persistent inflammation. Wound dressings not only improve the speed of wound healing, but also protect and cover the wound well. Hydrogels have the characteristics of good flexibility, high water content, and good biocompatibility, and are widely used in biomedicine and other fields. Common hydrogels are mainly natural hydrogels and synthetic hydrogels. Hydrogels cross-linked using different raw materials and different methods have different performance characteristics. Natural hydrogels prepared using polysaccharides are simple to obtain and have good biocompatibility, but are inferior to synthetic hydrogels in terms of mechanical properties and stability, and a single polysaccharide hydrogel cannot meet the component requirements for wound healing. Therefore, functional composite hydrogels with high mechanical properties, high biocompatibility, and high antibacterial properties are the current research hotspots. In this review, several common polysaccharides for hydrogel synthesis and the synthesis methods of polysaccharide hydrogels are introduced, and functional composite hydrogel dressings from recent years are classified. It is hoped that this can provide useful references for relevant research in this field.
50
Liang, Jianwei, Xiaoning Zhang, Zhenyu Chen, Shan Li und Chi Yan. „Thiol–Ene Click Reaction Initiated Rapid Gelation of PEGDA/Silk Fibroin Hydrogels“. Polymers 11, Nr. 12 (14.12.2019): 2102. http://dx.doi.org/10.3390/polym11122102.
Der volle Inhalt der QuelleAnnotation:
In this work, poly(ethylene glycol) diacrylate (PEGDA) molecules were grafted to silk fibroin (SF) molecules via a thiol–ene click reaction under 405 nm UV illumination for the fabrication of a PEGDA/SF composite hydrogel. The composite hydrogels could be prepared in a short and controllable gelation time without the use of a photoinitiator. Features relevant to the drug delivery of the PEGDA/SF hydrogels were assessed, and the hydrogels were characterized by various techniques. The results showed that the prepared PEGDA/SF hydrogels demonstrated a good sustained-release performance with limited swelling behavior. It was found that a prior cooling step can improve the compressive strength of the hydrogels effectively. Additionally, the MTT assay indicated the prepared PEGDA/SF hydrogel is non-cytotoxic. Subcutaneous implantation of the PEGDA/SF hydrogel in Kunming mice did not induce an obvious inflammation, which revealed that the prepared PEGDA/SF hydrogel possessed good biocompatibility. Furthermore, the mechanism of the gelation process was discussed.