David Průša, Stanislav Šťastník, Kateřina Svobodová, Karel Šuhajda, Zuzana Sochorová
The present work analyzes the effect of releasing physically bound water from hydrogel, cork, perlite, and ceramsite on materials exposed to microwave radiation and subsequently investigates possible changes in the physical properties of these materials (water absorption and thermal conductivity coefficient). The release of physically bound water from individual materials has potential practical applications in materials engineering, for example, in the internal curing of concrete, where individual aggregates could, under the influence of microwave radiation, release water into the structure of the concrete and thus further cure it. Experimental analysis was carried out with samples of the above-mentioned materials, which were first weighed and then immersed in water for 24 h. Then, they were weighed again and exposed to microwave radiation. After exposure, the samples were weighed again, left immersed in water for 24 h, and weighed again. The focus of the study was on the ability of the aggregates to release water due to microwave radiation and on the changes in the properties (water absorption, thermal conductivity coefficient) of these materials when exposed to microwave radiation. The samples were further monitored by digital microscopy for possible changes in the surface layer of the materials. The hydrogels show the highest water absorption (1000%) and the fastest water release (45 min to complete desiccation). After the release of water due to microwave radiation, their ability to absorb water is maintained. Of interest, however, is that in the case of almost complete removal of water from the soaked hydrogel, the original powdered state of the hydrogel is not obtained, but the outcome has rather a solid structure. In the case of cork, the water absorption depends on the fraction of the material.
{"title":"Effect of Microwave Radiation on the Properties of Hydrogel, Cork, Perlite, and Ceramsite.","authors":"David Průša, Stanislav Šťastník, Kateřina Svobodová, Karel Šuhajda, Zuzana Sochorová","doi":"10.3390/gels10080543","DOIUrl":"10.3390/gels10080543","url":null,"abstract":"<p><p>The present work analyzes the effect of releasing physically bound water from hydrogel, cork, perlite, and ceramsite on materials exposed to microwave radiation and subsequently investigates possible changes in the physical properties of these materials (water absorption and thermal conductivity coefficient). The release of physically bound water from individual materials has potential practical applications in materials engineering, for example, in the internal curing of concrete, where individual aggregates could, under the influence of microwave radiation, release water into the structure of the concrete and thus further cure it. Experimental analysis was carried out with samples of the above-mentioned materials, which were first weighed and then immersed in water for 24 h. Then, they were weighed again and exposed to microwave radiation. After exposure, the samples were weighed again, left immersed in water for 24 h, and weighed again. The focus of the study was on the ability of the aggregates to release water due to microwave radiation and on the changes in the properties (water absorption, thermal conductivity coefficient) of these materials when exposed to microwave radiation. The samples were further monitored by digital microscopy for possible changes in the surface layer of the materials. The hydrogels show the highest water absorption (1000%) and the fastest water release (45 min to complete desiccation). After the release of water due to microwave radiation, their ability to absorb water is maintained. Of interest, however, is that in the case of almost complete removal of water from the soaked hydrogel, the original powdered state of the hydrogel is not obtained, but the outcome has rather a solid structure. In the case of cork, the water absorption depends on the fraction of the material.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079995","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Osteonecrosis of the femoral head (ONFH) is a vascular disease of unknown etiology and can be categorized mainly into two types: non-traumatic and traumatic ONFH. Thus, understanding osteogenic-angiogenic coupling is of prime importance in finding a solution for the treatment of ONFH. Hydrogels are biomaterials that are similar to the extracellular matrix (ECM). As they are able to mimic real tissue, they meet one of the most important rules in tissue engineering. In ONFH studies, hydrogels have recently become popular because of their ability to retain water and their adjustable properties, injectability, and mimicry of natural ECM. Because bone regeneration and graft materials are very broad areas of research and ONFH is a complex situation including bone and vascular systems, and there is no settled treatment strategy for ONFH worldwide, in this review paper, we followed a top-down approach by reviewing (1) bone and bone grafting, (2) hydrogels, (3) vascular systems, and (4) ONFH and hydrogel use in ONFH with studies in the literature which show promising results in limited clinical studies. The aim of this review paper is to provide the reader with general information on every aspect of ONFH and to focus on the hydrogel used in ONFH.
{"title":"Hydrogel Use in Osteonecrosis of the Femoral Head.","authors":"Zeynep Bal, Nobuyuki Takakura","doi":"10.3390/gels10080544","DOIUrl":"10.3390/gels10080544","url":null,"abstract":"<p><p>Osteonecrosis of the femoral head (ONFH) is a vascular disease of unknown etiology and can be categorized mainly into two types: non-traumatic and traumatic ONFH. Thus, understanding osteogenic-angiogenic coupling is of prime importance in finding a solution for the treatment of ONFH. Hydrogels are biomaterials that are similar to the extracellular matrix (ECM). As they are able to mimic real tissue, they meet one of the most important rules in tissue engineering. In ONFH studies, hydrogels have recently become popular because of their ability to retain water and their adjustable properties, injectability, and mimicry of natural ECM. Because bone regeneration and graft materials are very broad areas of research and ONFH is a complex situation including bone and vascular systems, and there is no settled treatment strategy for ONFH worldwide, in this review paper, we followed a top-down approach by reviewing (1) bone and bone grafting, (2) hydrogels, (3) vascular systems, and (4) ONFH and hydrogel use in ONFH with studies in the literature which show promising results in limited clinical studies. The aim of this review paper is to provide the reader with general information on every aspect of ONFH and to focus on the hydrogel used in ONFH.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353442/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiaoye He, Shuang Ren, Hu Li, Di Han, Tianxin Liu, Meishan Wu, Jing Wang
In order to explore the formation mechanism of the emulsion gel induced by high pressure processing (HPP) and its encapsulation and protection of functional ingredients, a curcumin-loaded whey protein isolate (WPI)/κ-carrageenan (κ-CG) composite emulsion gel induced by HPP was prepared. The effect of pressure (400, 500 and 600 MPa), holding time (10, 20 and 30 min) and concentration of κ-CG (0.8%, 1.0% and 1.2%, w/v) on the swelling rate, gel strength, the stability of curcumin in the emulsion gel, water distribution and its mobility, as well as the contents of interface protein were characterized. The results showed that the addition of κ-CG significantly reduced the protein concentration required for the formation of emulsion gel induced by HPP and greatly reduced the swelling rate of the emulsion gel. The gel strength and storage stability of the composite emulsion gels increased with the increase in pressure (400-600 MPa) and holding time (10-30 min). When the pressure increased to 500 MPa, the stability of curcumin in the emulsion gel significantly improved. When the ratio of WPI to κ-CG was 12:1 (the κ-CG concentration was 1.0%), both the photochemical and thermal stability of curcumin were higher than those of the other two ratios. The HPP significantly increased the mobility of monolayer water in the system, while the mobility of multilayer water and immobilized water was significantly reduced. Increasing the holding time and the concentration of κ-CG both can result in an increase in the interfacial protein content in the oil/water system, and the HPP treatment had a significant effect on the composition of the interfacial protein of the emulsion gel.
{"title":"Preparation, Characterization and Formation Mechanism of High Pressure-Induced Whey Protein Isolate/κ-Carrageenan Composite Emulsion Gel Loaded with Curcumin.","authors":"Xiaoye He, Shuang Ren, Hu Li, Di Han, Tianxin Liu, Meishan Wu, Jing Wang","doi":"10.3390/gels10080542","DOIUrl":"10.3390/gels10080542","url":null,"abstract":"<p><p>In order to explore the formation mechanism of the emulsion gel induced by high pressure processing (HPP) and its encapsulation and protection of functional ingredients, a curcumin-loaded whey protein isolate (WPI)/κ-carrageenan (κ-CG) composite emulsion gel induced by HPP was prepared. The effect of pressure (400, 500 and 600 MPa), holding time (10, 20 and 30 min) and concentration of κ-CG (0.8%, 1.0% and 1.2%, <i>w</i>/<i>v</i>) on the swelling rate, gel strength, the stability of curcumin in the emulsion gel, water distribution and its mobility, as well as the contents of interface protein were characterized. The results showed that the addition of κ-CG significantly reduced the protein concentration required for the formation of emulsion gel induced by HPP and greatly reduced the swelling rate of the emulsion gel. The gel strength and storage stability of the composite emulsion gels increased with the increase in pressure (400-600 MPa) and holding time (10-30 min). When the pressure increased to 500 MPa, the stability of curcumin in the emulsion gel significantly improved. When the ratio of WPI to κ-CG was 12:1 (the κ-CG concentration was 1.0%), both the photochemical and thermal stability of curcumin were higher than those of the other two ratios. The HPP significantly increased the mobility of monolayer water in the system, while the mobility of multilayer water and immobilized water was significantly reduced. Increasing the holding time and the concentration of κ-CG both can result in an increase in the interfacial protein content in the oil/water system, and the HPP treatment had a significant effect on the composition of the interfacial protein of the emulsion gel.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353826/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Lazaro Ruiz-Virgen, Miguel Angel Hernandez-Martinez, Gabriela Martínez-Mejía, Rubén Caro-Briones, Enrique Herbert-Pucheta, José Manuel Del Río, Mónica Corea
The pH- and thermo-responsive behavior of polymeric hydrogels MC-co-MA have been studied in detail using dynamic light scattering DLS, scanning electron microscopy SEM, nuclear magnetic resonance (1H NMR) and rheology to evaluate the conformational changes, swelling-shrinkage, stability, the ability to flow and the diffusion process of nanoparticles at several temperatures. Furthermore, polymeric systems functionalized with acrylic acid MC and acrylamide MA were subjected to a titration process with a calcium chloride CaCl2 solution to analyze its effect on the average particle diameter Dz, polymer structure and the intra- and intermolecular interactions in order to provide a responsive polymer network that can be used as a possible nanocarrier for drug delivery with several benefits. The results confirmed that the structural changes in the sensitive hydrogels are highly dependent on the corresponding critical solution temperature CST of the carboxylic (-COOH) and amide (-CONH2) functional groups and the influence of calcium ions Ca2+ on the formation or breaking of hydrogen bonds, as well as the decrease in electrostatic repulsions generated between the polymer chains contributing to a particle agglomeration phenomenon. The temperature leads to a re-arrangement of the polymer chains, affecting the viscoelastic properties of the hydrogels. In addition, the diffusion coefficients D of nanoparticles were evaluated, showing a closeness among with the morphology, shape, size and temperature, resulting in slower diffusions for larger particles size and, conversely, the diffusion in the medium increasing as the polymer size is reduced. Therefore, the hydrogels exhibited a remarkable response to pH and temperature variations in the environment. During this research, the functionality and behavior of the polymeric nanoparticles were observed under different analysis conditions, which revealed notable structural changes and further demonstrated the nanoparticles promising high potential for drug delivery applications. Hence, these results have sparked significant interest in various scientific, industrial and technological fields.
利用动态光散射 DLS、扫描电子显微镜 SEM、核磁共振 (1H NMR) 和流变学详细研究了聚合物水凝胶 MC-co-MA 的 pH 和热响应行为,以评估纳米粒子在不同温度下的构象变化、溶胀收缩、稳定性、流动能力和扩散过程。此外,还用氯化钙 CaCl2 溶液对丙烯酸 MC 和丙烯酰胺 MA 功能化聚合物体系进行了滴定处理,以分析其对平均颗粒直径 Dz、聚合物结构以及分子内和分子间相互作用的影响,从而提供一种可用作纳米载体的响应性聚合物网络,用于药物输送并带来多种益处。研究结果证实,敏感水凝胶的结构变化高度依赖于羧酸(-COOH)和酰胺(-CONH2)官能团的相应临界溶液温度 CST、钙离子 Ca2+ 对氢键形成或断裂的影响,以及聚合物链之间产生的静电排斥力的降低,这些因素都会导致微粒团聚现象。温度会导致聚合物链重新排列,从而影响水凝胶的粘弹性能。此外,还对纳米颗粒的扩散系数 D 进行了评估,结果表明其与形态、形状、大小和温度的关系密切,颗粒越大,扩散速度越慢,反之,随着聚合物尺寸的减小,在介质中的扩散速度也会增加。因此,水凝胶对环境中的酸碱度和温度变化有显著的反应。在这项研究中,我们观察了聚合物纳米粒子在不同分析条件下的功能和行为,发现了显著的结构变化,进一步证明了纳米粒子在药物输送应用方面的巨大潜力。因此,这些成果引发了科学、工业和技术领域的极大兴趣。
{"title":"Analysis of Structural Changes of pH-Thermo-Responsive Nanoparticles in Polymeric Hydrogels.","authors":"Lazaro Ruiz-Virgen, Miguel Angel Hernandez-Martinez, Gabriela Martínez-Mejía, Rubén Caro-Briones, Enrique Herbert-Pucheta, José Manuel Del Río, Mónica Corea","doi":"10.3390/gels10080541","DOIUrl":"10.3390/gels10080541","url":null,"abstract":"<p><p>The pH- and thermo-responsive behavior of polymeric hydrogels MC-co-MA have been studied in detail using dynamic light scattering DLS, scanning electron microscopy SEM, nuclear magnetic resonance (<sup>1</sup>H NMR) and rheology to evaluate the conformational changes, swelling-shrinkage, stability, the ability to flow and the diffusion process of nanoparticles at several temperatures. Furthermore, polymeric systems functionalized with acrylic acid MC and acrylamide MA were subjected to a titration process with a calcium chloride CaCl2 solution to analyze its effect on the average particle diameter Dz, polymer structure and the intra- and intermolecular interactions in order to provide a responsive polymer network that can be used as a possible nanocarrier for drug delivery with several benefits. The results confirmed that the structural changes in the sensitive hydrogels are highly dependent on the corresponding critical solution temperature CST of the carboxylic (-COOH) and amide (-CONH<sub>2</sub>) functional groups and the influence of calcium ions Ca2+ on the formation or breaking of hydrogen bonds, as well as the decrease in electrostatic repulsions generated between the polymer chains contributing to a particle agglomeration phenomenon. The temperature leads to a re-arrangement of the polymer chains, affecting the viscoelastic properties of the hydrogels. In addition, the diffusion coefficients D of nanoparticles were evaluated, showing a closeness among with the morphology, shape, size and temperature, resulting in slower diffusions for larger particles size and, conversely, the diffusion in the medium increasing as the polymer size is reduced. Therefore, the hydrogels exhibited a remarkable response to pH and temperature variations in the environment. During this research, the functionality and behavior of the polymeric nanoparticles were observed under different analysis conditions, which revealed notable structural changes and further demonstrated the nanoparticles promising high potential for drug delivery applications. Hence, these results have sparked significant interest in various scientific, industrial and technological fields.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353694/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079986","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jonad L A Contarato, Geisa N Barbalho, Marcilio Cunha-Filho, Guilherme M Gelfuso, Tais Gratieri
The OphthalMimic is a 3D-printed device that simulates human ocular conditions with artificial lacrimal flow, cul-de-sac area, moving eyelid, and a surface to interact with ophthalmic formulations. All tests with such a device have used a continuous artificial tear flow rate of 1 mL/min for 5 min. Here, we implemented protocol variations regarding the application time and simulated tear flow to increase the test's discrimination and achieve reliable performance results. The new protocols incorporated the previously evaluated 0.2% fluconazole formulations containing or not chitosan as a mucoadhesive component (PLX16CS10 and PLX16, respectively) and novel moxifloxacin 5% formulations, either in a conventional formulation and a microemulsion (CONTROL and NEMOX, respectively). The flow rate was reduced by 50%, and a pre-flow application period was also included to allow formulation interaction with the membrane. The OphthalMimic model was used with both polymeric and hydrogel-based hybrid membranes, including a simulated eyelid. Lowering the flow made it feasible to prolong the testing duration, enhancing device discrimination potential. The hydrogel membrane was adequate for testing nanostructure formulations. The OphthalMimic device demonstrated once again to be a versatile method for evaluating the performance of ophthalmic drug formulations with the potential of reducing the use of animals for experimentation.
{"title":"Applying Different Conditions in the OphthalMimic Device Using Polymeric and Hydrogel-Based Hybrid Membranes to Evaluate Gels and Nanostructured Ophthalmic Formulations.","authors":"Jonad L A Contarato, Geisa N Barbalho, Marcilio Cunha-Filho, Guilherme M Gelfuso, Tais Gratieri","doi":"10.3390/gels10080538","DOIUrl":"10.3390/gels10080538","url":null,"abstract":"<p><p>The OphthalMimic is a 3D-printed device that simulates human ocular conditions with artificial lacrimal flow, cul-de-sac area, moving eyelid, and a surface to interact with ophthalmic formulations. All tests with such a device have used a continuous artificial tear flow rate of 1 mL/min for 5 min. Here, we implemented protocol variations regarding the application time and simulated tear flow to increase the test's discrimination and achieve reliable performance results. The new protocols incorporated the previously evaluated 0.2% fluconazole formulations containing or not chitosan as a mucoadhesive component (PLX16CS10 and PLX16, respectively) and novel moxifloxacin 5% formulations, either in a conventional formulation and a microemulsion (CONTROL and NEMOX, respectively). The flow rate was reduced by 50%, and a pre-flow application period was also included to allow formulation interaction with the membrane. The OphthalMimic model was used with both polymeric and hydrogel-based hybrid membranes, including a simulated eyelid. Lowering the flow made it feasible to prolong the testing duration, enhancing device discrimination potential. The hydrogel membrane was adequate for testing nanostructure formulations. The OphthalMimic device demonstrated once again to be a versatile method for evaluating the performance of ophthalmic drug formulations with the potential of reducing the use of animals for experimentation.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353903/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079987","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Building fire will seriously threaten human safety. Silica aerogel with low thermal conductivity and thermal stability as fire-retardant material has been widely used in building fireproof structures. However, the natural fragility of silica aerogel will limit its application. In this work, the effects of faults on the thermal stability of silica aerogel are studied by molecular dynamics simulation with large simulation time (20 ns). Additionally, the atomic model of silica aerogel with random faults is built by a straining structure (tensile strains are 10%, 20%, 30%, and 40%). It is found that when the tensile strain is less than 20%, the silica backbone can remain stable. The effects of faults on the thermal stability can be neglected. The silica backbone thermally vibrates during the heating process. However, when the tensile strain is over 30%, it is observed that the faults will enhance the silica backbone merging. Silica aerogel can be stable under 800 K. It is believed that the results of this study will pave the way for the development of fireproof materials.
{"title":"Evolution Process of Fault Silica Aerogel under High Temperatures: A Molecular Dynamics Approach.","authors":"Wenping Yue, Tao Luo, Kaide Liu","doi":"10.3390/gels10080539","DOIUrl":"10.3390/gels10080539","url":null,"abstract":"<p><p>Building fire will seriously threaten human safety. Silica aerogel with low thermal conductivity and thermal stability as fire-retardant material has been widely used in building fireproof structures. However, the natural fragility of silica aerogel will limit its application. In this work, the effects of faults on the thermal stability of silica aerogel are studied by molecular dynamics simulation with large simulation time (20 ns). Additionally, the atomic model of silica aerogel with random faults is built by a straining structure (tensile strains are 10%, 20%, 30%, and 40%). It is found that when the tensile strain is less than 20%, the silica backbone can remain stable. The effects of faults on the thermal stability can be neglected. The silica backbone thermally vibrates during the heating process. However, when the tensile strain is over 30%, it is observed that the faults will enhance the silica backbone merging. Silica aerogel can be stable under 800 K. It is believed that the results of this study will pave the way for the development of fireproof materials.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11354013/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079999","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Luis M Vidal-Flores, Miguel Reyes-Alberto, Efraín Albor-Ramírez, César F Domínguez-Velasco, Enoch Gutierrez-Herrera, Miguel A Padilla-Castañeda
Recreating cerebral tissue using a tissue-mimicking phantom is valuable because it provides a tool for studying physiological and biological processes related to tissues without the necessity of performing the study directly in the tissue or even in a patient. The reproduction of the optical properties allows investigation in areas such as imaging, optics, and ultrasound, among others. This paper presents a methodology for manufacturing agarose-based phantoms that mimic the optical characteristics of brain tissue using scattering and absorbing agents and proposes combinations of these agents to recreate the healthy brain tissue optical coefficients within the wavelength range of 350 to 500 nm. The results of the characterization of the manufactured phantoms propose ideal combinations of the used materials for their use in controlled environment experiments in the UV range, following a cost-effective methodology.
{"title":"Fabrication and Characterization of Brain Tissue Phantoms Using Agarose Gels for Ultraviolet Vision Systems.","authors":"Luis M Vidal-Flores, Miguel Reyes-Alberto, Efraín Albor-Ramírez, César F Domínguez-Velasco, Enoch Gutierrez-Herrera, Miguel A Padilla-Castañeda","doi":"10.3390/gels10080540","DOIUrl":"10.3390/gels10080540","url":null,"abstract":"<p><p>Recreating cerebral tissue using a tissue-mimicking phantom is valuable because it provides a tool for studying physiological and biological processes related to tissues without the necessity of performing the study directly in the tissue or even in a patient. The reproduction of the optical properties allows investigation in areas such as imaging, optics, and ultrasound, among others. This paper presents a methodology for manufacturing agarose-based phantoms that mimic the optical characteristics of brain tissue using scattering and absorbing agents and proposes combinations of these agents to recreate the healthy brain tissue optical coefficients within the wavelength range of 350 to 500 nm. The results of the characterization of the manufactured phantoms propose ideal combinations of the used materials for their use in controlled environment experiments in the UV range, following a cost-effective methodology.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353431/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142080000","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Adel Ashery, Ahmed E H Gaballah, Gamal M Turky, Mohamed A Basyooni-Murat Kabatas
The current work presents a new structure based on Au/PVA/SiO2/p-Si/Al that has not been studied before. An aqueous solution of polyvinyl alcohol (PVA) polymer gel was deposited on the surface of SiO2/Si using the spin-coating technique. The silicon wafer was left to be oxidized in a furnace at 1170 k for thirty minutes, creating an interdiffusion layer of SiO2. The variations in the dielectric constant (Є'), dielectric loss (Є″), and dielectric tangent (tanδ) with the change in the frequency, voltage, and temperature were analyzed. The results showed an increase in the dielectric constant (Є') and a decrease in the dielectric loss (Є″) and tangent (tanδ); thus, the Au/PVA/SiO2/p-Si/Al heterostructure has opened up new frontiers for the semiconductor industry, especially for capacitor manufacturing. The Cole-Cole diagrams of the Є″ and Є' have been investigated at different temperatures and voltages. The ideality factor (n), barrier height (Φb), series resistance (Rs), shunt resistance (Rsh), and rectification ratio (RR) were also measured at different temperatures.
本研究提出了一种基于 Au/PVA/SiO2/p-Si/Al 的新结构,这种结构以前从未研究过。采用旋涂技术将聚乙烯醇(PVA)聚合物凝胶水溶液沉积在二氧化硅/硅表面。硅晶片在 1170 k 的熔炉中氧化 30 分钟,形成二氧化硅相互扩散层。分析了介电常数(Є')、介电损耗(Є″)和介电正切(tanδ)随频率、电压和温度变化的变化情况。结果表明,介电常数(Є')增大,介电损耗(Є″)和正切(tanδ)减小;因此,Au/PVA/SiO2/p-Si/Al 异质结构为半导体工业,尤其是电容器制造开辟了新的领域。我们研究了不同温度和电压下Є″和Є'的科尔-科尔图。此外,还测量了不同温度下的意向系数(n)、势垒高度(Φb)、串联电阻(Rs)、并联电阻(Rsh)和整流比(RR)。
{"title":"Gel-Based PVA/SiO<sub>2</sub>/p-Si Heterojunction for Electronic Device Applications.","authors":"Adel Ashery, Ahmed E H Gaballah, Gamal M Turky, Mohamed A Basyooni-Murat Kabatas","doi":"10.3390/gels10080537","DOIUrl":"10.3390/gels10080537","url":null,"abstract":"<p><p>The current work presents a new structure based on Au/PVA/SiO<sub>2</sub>/p-Si/Al that has not been studied before. An aqueous solution of polyvinyl alcohol (PVA) polymer gel was deposited on the surface of SiO<sub>2</sub>/Si using the spin-coating technique. The silicon wafer was left to be oxidized in a furnace at 1170 k for thirty minutes, creating an interdiffusion layer of SiO<sub>2</sub>. The variations in the dielectric constant (Є'), dielectric loss (Є″), and dielectric tangent (tanδ) with the change in the frequency, voltage, and temperature were analyzed. The results showed an increase in the dielectric constant (Є') and a decrease in the dielectric loss (Є″) and tangent (tanδ); thus, the Au/PVA/SiO<sub>2</sub>/p-Si/Al heterostructure has opened up new frontiers for the semiconductor industry, especially for capacitor manufacturing. The Cole-Cole diagrams of the Є″ and Є' have been investigated at different temperatures and voltages. The ideality factor (n), barrier height (Φ<sub>b</sub>), series resistance (R<sub>s</sub>), shunt resistance (R<sub>sh</sub>), and rectification ratio (RR) were also measured at different temperatures.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353532/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142080002","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
When encountering heavy oil reservoirs during drilling, due to the change in pressure difference inside the well, heavy oil will invade the drilling fluid, and drilling fluid will spill into the reservoir along the formation fractures, affecting the drilling process. A supramolecular polymer gel-based temporary plugging agent was prepared using acrylamide (AM), butyl acrylate (BA), and styrene (ST) as reacting monomers, N, N-methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and poly(vinyl alcohol) (PVA) as a non-covalent component. A supermolecular polymer gel with a temperature tolerance of 120 °C and acid solubility of 90% was developed. The experimental results demonstrated that a mechanically robust, thermally stable supramolecular polymer gel was successfully synthesized through the copolymerization of AM, BA, and ST, as well as the in situ formation hydrogen bonding between poly (AM-co-BA-co-ST) and PVA, leading to a three-dimensional entangled structure. The gel-forming solution possessed excellent gelling performance even in the presence of a high content of salt and heavy oil, demonstrating superior resistance to salt and heavy oil under harsh reservoir conditions. High-temperature and high-pressure plugging displacement experiments proved that the supramolecular polymer gel exhibited high pressure-bearing capacity, and the blocking strength reached 5.96 MPa in a wedge-shaped fracture with a length of 30 cm. Furthermore, the dissolution rate of the supramolecular polymer gel was as high as 96.2% at 120 °C for 48 h under a 15% HCl solution condition.
{"title":"Preparation and Performance Evaluation of a Supramolecular Polymer Gel-Based Temporary Plugging Agent for Heavy Oil Reservoir.","authors":"Cheng Niu, Sheng Fan, Xiuping Chen, Zhong He, Liyao Dai, Zhibo Wen, Meichun Li","doi":"10.3390/gels10080536","DOIUrl":"10.3390/gels10080536","url":null,"abstract":"<p><p>When encountering heavy oil reservoirs during drilling, due to the change in pressure difference inside the well, heavy oil will invade the drilling fluid, and drilling fluid will spill into the reservoir along the formation fractures, affecting the drilling process. A supramolecular polymer gel-based temporary plugging agent was prepared using acrylamide (AM), butyl acrylate (BA), and styrene (ST) as reacting monomers, N, N-methylenebisacrylamide (MBA) as a crosslinking agent, ammonium persulfate (APS) as an initiator, and poly(vinyl alcohol) (PVA) as a non-covalent component. A supermolecular polymer gel with a temperature tolerance of 120 °C and acid solubility of 90% was developed. The experimental results demonstrated that a mechanically robust, thermally stable supramolecular polymer gel was successfully synthesized through the copolymerization of AM, BA, and ST, as well as the in situ formation hydrogen bonding between poly (AM-co-BA-co-ST) and PVA, leading to a three-dimensional entangled structure. The gel-forming solution possessed excellent gelling performance even in the presence of a high content of salt and heavy oil, demonstrating superior resistance to salt and heavy oil under harsh reservoir conditions. High-temperature and high-pressure plugging displacement experiments proved that the supramolecular polymer gel exhibited high pressure-bearing capacity, and the blocking strength reached 5.96 MPa in a wedge-shaped fracture with a length of 30 cm. Furthermore, the dissolution rate of the supramolecular polymer gel was as high as 96.2% at 120 °C for 48 h under a 15% HCl solution condition.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11354005/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142079961","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Biopolymer gels have gained tremendous potential for therapeutic applications due to their biocompatibility, biodegradability, and ability to adsorb and bind biological fluids, making them attractive for drug delivery and therapy. In this study, the versatility of biopolymer gels is explored in theranostic backgrounds, with a focus on integrating imaging features and facilitating real-time monitoring of drug delivery. Different methods of delivery are explored for incorporating imaging agents into biopolymer gels, including encapsulation, surface functionalization, nanoparticle encapsulation, and layer-by-layer assembly techniques. These methods exhibit the integration of agents and real-time monitoring drug delivery. We summarize the synthesis methods, general properties, and functional mechanisms of biopolymer gels, demonstrating their broad applications as multimodal systems for imaging-based therapeutics. These techniques not only enable multiple imaging but also provide signal enhancement and facilitate imaging targets, increasing the diagnostic accuracy and therapeutic efficacy. In addition, current techniques for incorporating imaging agents into biopolymer gels are discussed, as well as their role in precise drug delivery and monitoring.
{"title":"Harnessing Biopolymer Gels for Theranostic Applications: Imaging Agent Integration and Real-Time Monitoring of Drug Delivery.","authors":"Pranita Jirvankar, Surendra Agrawal, Nikhita Chambhare, Rishabh Agrawal","doi":"10.3390/gels10080535","DOIUrl":"10.3390/gels10080535","url":null,"abstract":"<p><p>Biopolymer gels have gained tremendous potential for therapeutic applications due to their biocompatibility, biodegradability, and ability to adsorb and bind biological fluids, making them attractive for drug delivery and therapy. In this study, the versatility of biopolymer gels is explored in theranostic backgrounds, with a focus on integrating imaging features and facilitating real-time monitoring of drug delivery. Different methods of delivery are explored for incorporating imaging agents into biopolymer gels, including encapsulation, surface functionalization, nanoparticle encapsulation, and layer-by-layer assembly techniques. These methods exhibit the integration of agents and real-time monitoring drug delivery. We summarize the synthesis methods, general properties, and functional mechanisms of biopolymer gels, demonstrating their broad applications as multimodal systems for imaging-based therapeutics. These techniques not only enable multiple imaging but also provide signal enhancement and facilitate imaging targets, increasing the diagnostic accuracy and therapeutic efficacy. In addition, current techniques for incorporating imaging agents into biopolymer gels are discussed, as well as their role in precise drug delivery and monitoring.</p>","PeriodicalId":12506,"journal":{"name":"Gels","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11353668/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142080003","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}