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1.
Int J Biol Macromol ; 280(Pt 1): 135769, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39299424

RESUMO

In this paper, the capabilities of NIR spectroscopy and LF-NMR data were compared for rapidly predicting the rheological properties of polysaccharide gels and assessing their printability. Seven machine learning (ML) models were established for rheological property prediction based on partial least squares regression (PLSR), support vector regression (SVR), back propagation artificial neural network (BPANN), one-dimensional convolutional neural network (1D CNN), recurrent neural network (RNN), long short-term memory (LSTM), and Transformer. The results showed that among the seven models, the SVR, BPANN, and 1D CNN models based on NIR spectroscopy effectively predicted the rheological parameters of polysaccharide gels, with the highest R2 in the prediction set reaching 0.9796 and the highest RPD reaching 7.0708. For most polysaccharide gels, using the LF-NMR relaxation time distribution curves provided better predictions of rheological properties than using transverse relaxation time and peak area. Among the seven models, the PLSR, SVR, 1D CNN, and Transformer models effectively predicted the rheological characteristics based on LF-NMR parameters, with the highest R2 in the prediction set reaching 0.9869 and the highest RPD reaching 8.7220. This study successfully established a prediction system for the rheological behaviors and 3D printing performance of polysaccharide gels using NIR spectroscopy and LF-NMR data combined with ML methods, achieving an intelligent assessment of the 3D printing behavior of polysaccharide gels.

2.
Commun Mater ; 5(1): 197, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39309138

RESUMO

Nanofiber-based hydrogel delivery systems have recently shown great potential in biomedical applications, specifically due to their high surface-to-volume ratio of ultra-fine nanofibers and their ability to carry low solubility drugs. Herein, we introduce a visible light-triggered in situ-gelling drug vehicle (GAP Gel) composed of ascorbyl palmitate (AP) nanofibers and gelatin methacryloyl polymer. AP nanofibers form self-assembled structures through intermolecular interactions with a hydrophobic drug-loading core. We demonstrate that the hydrophilic periphery of AP nanofibers allows them to interact with other hydrophilic molecules via hydrogen bonds. The presence of AP nanofibers significantly enhances the viscoelasticity of GAP Gel in a concentration-dependent manner. Further, GAP Gel shows in vitro biocompatibility and sustained drug delivery efficacy when loaded with a hydrophobic antibiotic. Likewise, GAP Gel shows excellent in vivo biocompatibility when implanted in immunocompetent mice in various forms. Lastly, GAP Gels maintain cell viability when cultured in a 3D-environment over 7 days, establishing it as a promising and versatile hydrogel platform for the delivery of biotherapeutics.

3.
ACS Appl Mater Interfaces ; 16(37): 48927-48936, 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39238144

RESUMO

Ionic gels are emerging as a promising solution for improving the functionality of electrochromic devices. They are increasingly drawing attention in the fields of electrochemistry and functional materials due to their potential to address issues associated with traditional liquid electrolytes, such as volatility, toxicity, and leakage. In extreme scenarios and/or the design of flexible devices, ionic gel electrolytes offer unique and invaluable advantages. This perspective delves into the application of ionic gels in electrochromic devices, exploring various methods to enhance their performance. After briefly introducing developments in ionic gels for electrochromic devices, the trends and key points of future development are discussed in detail.

4.
Polymers (Basel) ; 16(17)2024 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-39274091

RESUMO

The progress in polymer science and nanotechnology yields new colloidal and macromolecular objects and their combinations, which can be defined as complex polymer materials. The complexity may include a complicated composition and architecture of macromolecular chains, specific intermolecular interactions, an unusual phase behavior, and a structure of a multi-component polymer-containing material. Determination of a relation between the structure of a complex material, the structure and properties of its constituent elements, and the rheological properties of the material as a whole is the subject of structural rheology-a valuable tool for the development and study of novel materials. This work summarizes the author's structural-rheological studies of complex polymer materials for determining the conditions and rheo-manifestations of their micro- and nanostructuring. The complicated chemical composition of macromolecular chains and its role in polymer structuring via block segregation and cooperative hydrogen bonds in melt and solutions is considered using tri- and multiblock styrene/isoprene and vinyl acetate/vinyl alcohol copolymers. Specific molecular interactions are analyzed in solutions of cellulose; its acetate butyrate; a gelatin/carrageenan combination; and different acrylonitrile, oxadiazole, and benzimidazole copolymers. A homogeneous structuring may result from a conformational transition, a mesophase formation, or a macromolecular association caused by a complex chain composition or specific inter- and supramolecular interactions, which, however, may be masked by macromolecular entanglements when determining a rheological behavior. A heterogeneous structure formation implies a microscopic phase separation upon non-solvent addition, temperature change, or intense shear up to a macroscopic decomposition. Specific polymer/particle interactions have been examined using polyethylene oxide solutions, polyisobutylene melts, and cellulose gels containing solid particles of different nature, demonstrating the competition of macromolecular entanglements, interparticle interactions, and adsorption polymer/particle bonds in governing the rheological properties. Complex chain architecture has been considered using long-chain branched polybutylene-adipate-terephthalate and polyethylene melts, cross-linked sodium hyaluronate hydrogels, asphaltene solutions, and linear/highly-branched polydimethylsiloxane blends, showing that branching raises the viscosity and elasticity and can result in limited miscibility with linear isomonomer chains. Finally, some examples of composite adhesives, membranes, and greases as structured polymeric functional materials have been presented with the demonstration of the relation between their rheological and performance properties.

5.
Materials (Basel) ; 17(17)2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39274827

RESUMO

1H spin-lattice relaxation experiments have been performed for gels based on fish collagen in order to analyze water dynamics. The covered frequency range ranges from 10 kHz to 10 MHz; in some cases, the temperature has varied as well. The relaxation data have been reproduced in terms of two models of water motion-a model including two relaxation contributions associated with the diffusion of water molecules on the macromolecular surfaces and a second model being just a phenomenological power law. The concept of surface diffusion has led to a very good agreement with the experimental data and a consistent set of parameters, with the diffusion coefficients being about five orders of magnitude slower compared to bulk water for one of the pools and considerably faster for the second one (smaller by factors between 2 and 20 compared to bulk water). In some cases, the attempt to reproduce the data in terms of a power law has led to a good agreement with the experimental data (the power law factor varying between 0.41 and 0.57); however, in other cases, the discrepancies are significant. This outcome favors the concept of surface diffusion.

6.
ACS Nano ; 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39321316

RESUMO

Soft gels, formed via the self-assembly of particulate materials, exhibit intricate multiscale structures that provide them with flexibility and resilience when subjected to external stresses. This work combines particle simulations and topological data analysis (TDA) to characterize the complex multiscale structure of soft gels. Our TDA analysis focuses on the use of the Euler characteristic, which is an interpretable and computationally scalable topological descriptor that is combined with filtration operations to obtain information on the geometric (local) and topological (global) structure of soft gels. We reduce the topological information obtained with TDA using principal component analysis (PCA) and show that this provides an informative low-dimensional representation of the gel structure. We use the proposed computational framework to investigate the influence of gel preparation (e.g., quench rate, volume fraction) on soft gel structure and to explore dynamic deformations that emerge under oscillatory shear in various response regimes (linear, nonlinear, and flow). Our analysis provides evidence of the existence of hierarchical structures in soft gels, which are not easily identifiable otherwise. Moreover, our analysis reveals direct correlations between topological changes of the gel structure under deformation and mechanical phenomena distinctive of gel materials, such as stiffening and yielding. In summary, we show that TDA facilitates the mathematical representation, quantification, and analysis of soft gel structures, extending traditional network analysis methods to capture both local and global organization.

7.
Food Res Int ; 195: 114944, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39277222

RESUMO

The gelation of milk proteins can be achieved by various means, enabling the development of diverse products. In this study, heat-set milk protein gels (15 % protein) of diverse textures were made by pH modulation and two gels were selected for dynamic in vitro gastric digestion: a spoonable soft gel (SG, pH 6.55' G' of ∼100 Pa) and a sliceable firm gel (FG, pH 5.65; G' of ∼7000 Pa). The two gels displayed markedly different structural changes and digestion kinetics during gastric digestion. The SG underwent substantial structural compaction during the first 120 min of gastric digestion into a denser and firmer gastric chyme (26.3 % crude protein, G* of ∼8500 Pa) than the chyme of the FG (15.7 % crude protein, G* of ∼3000 Pa). These contrasting intragastric structural changes of the gels reversed their original textural differences, which led to slower digestion and gastric emptying of proteins from the SG compared with the FG. The different intragastric pH profiles during the digestion of the two gels likely played a key role by modulating the proteolytic activity and specificity (to κ-casein) of pepsin. Preferential early cleavage of κ-casein in SG stimulated coagulation and compaction of solid chyme, whereas rapid hydrolysis of αS- and ß-caseins in the FG weakened coagulation. This study provided new insights into controlling the structural development of dairy-based foods during gastric digestion and modulating digestion kinetics.


Assuntos
Digestão , Géis , Temperatura Alta , Proteínas do Leite , Géis/química , Digestão/fisiologia , Concentração de Íons de Hidrogênio , Cinética , Proteínas do Leite/química , Proteínas do Leite/metabolismo , Esvaziamento Gástrico , Caseínas/química , Caseínas/metabolismo , Pepsina A/metabolismo , Animais , Manipulação de Alimentos/métodos , Proteólise
8.
Macromol Rapid Commun ; : e2400564, 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39254520

RESUMO

The kinetics of gelation in the Activators Regenerated by Electron Transfer Atom Transfer Radical Polymerization (ARGET ATRP) of styrene, using a bifunctional initiator and no crosslinking agents are investigated. By applying the method of moments, we develop a system of differential equations that accounts for the formation of polymer rings. The kinetic rate constants of this model are optimized on the experimentally determined kinetics, varying the reaction temperature and ethanol fraction. Subsequently, we explore how variations in the amounts of catalyst, initiator, and reducing agents affect the simulated equilibria of ARGET ATRP, the emergence of gelation, and the swelling properties of the resulting networks. These findings suggest that favoring ring formation enhances the gelation phenomenon, supporting the hypothesis that the networks formed under the reported reaction conditions are olympic gels.

9.
Int J Biol Macromol ; 279(Pt 3): 135397, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245115

RESUMO

Food gel is a kind of macromolecular biopolymer with viscoelasticity, which has good water retention and gelling ability, especially gels formed by protein and/or polysaccharide. The addition of calcium ions triggers gelation by interacting with the gel matrix, enhancing gels' textural and rheological properties like hardness, viscosity and elasticity. Thus calcium ions enrich the range of applications of food gels. This review focuses on forming a calcium-induced gel and improving the texture properties. It summarizes the mechanisms of gelation induced by calcium ions in polysaccharide, protein, and polysaccharide-protein systems and their gel properties. The effects of influencing factors in calcium ion concentration, types and mixing ratios of matrices, acid, and alkaline environments, as well as treatment methods on calcium-induced gel characteristics, are presented. Additionally, the current applications of calcium-induced gels in food industries and challenges are presented.

10.
Int J Pharm ; 664: 124599, 2024 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-39154917

RESUMO

Local anesthetics (LA), as part of multimodal analgesia, have garnered significant interest for their role in delaying the initiation of opioid therapy, reducing postoperative opioid usage, and mitigating both hospitalization duration and related expenses. Despite numerous endeavors to extend the duration of local anesthetic effects, achieving truly satisfactory long-acting analgesia remains elusive. Drawing upon prior investigations, vesicular phospholipid gels (VPGs) emerge as promising candidates for extended-release modalities in small-molecule drug delivery systems. Therefore, we tried to use the amphiphilicity of phospholipids to co-encapsulate levobupivacaine hydrochloride and meloxicam, two drugs with different hydrophilicity, to obtain a long-term synergistic analgesic effect. Initially, the physicochemical attributes of the formulation were characterized, followed by an examination of its in vitro release kinetics, substantiating the viability of extending the release duration of the dual drugs. Sequentially, in vivo investigations encompassing pharmacokinetic profiling and assessment of analgesic efficacy were undertaken, revealing a prolonged release duration of up to 120 h and attainment of optimal postoperative analgesia. Subsequently, inquiries into the mechanism underlying synergistic analgesic effects and safety evaluations pertinent to the delivery strategy were pursued. In summation, we successfully developed a promising formulation to achieve long-acting analgesia.


Assuntos
Anestésicos Locais , Preparações de Ação Retardada , Liberação Controlada de Fármacos , Levobupivacaína , Meloxicam , Dor Pós-Operatória , Dor Pós-Operatória/tratamento farmacológico , Anestésicos Locais/administração & dosagem , Anestésicos Locais/farmacocinética , Anestésicos Locais/química , Animais , Meloxicam/administração & dosagem , Meloxicam/farmacocinética , Masculino , Levobupivacaína/administração & dosagem , Fosfolipídeos/química , Fosfolipídeos/administração & dosagem , Ratos Sprague-Dawley , Bupivacaína/administração & dosagem , Bupivacaína/farmacocinética , Bupivacaína/química , Bupivacaína/análogos & derivados , Analgésicos/administração & dosagem , Analgésicos/química , Analgésicos/farmacocinética , Géis , Sinergismo Farmacológico
11.
Int J Biol Macromol ; 278(Pt 1): 134374, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39098671

RESUMO

The consumption of animal products has witnessed a significant increase over the years, leading to a growing need for industries to adopt strict waste control measures to mitigate environmental impacts. The disposal of animal waste in landfill can result in diverse and potentially hazardous decomposition by-products. Animal by-products, derived from meat, poultry, seafood and fish industries, offer a substantial raw material source for collagen and gelatin production due to their high protein content. Collagen, being a major protein component of animal tissues, represents an abundant resource that finds application in various chemical and material industries. The demand for collagen-based products continues to grow, yet the availability of primary material remains limited and insufficient to meet projected needs. Consequently, repurposing waste materials that contain collagen provides an opportunity to meet this need while at the same time minimizing the amount of waste that is dumped. This review examines the potential to extract value from the collagen content present in animal-derived waste and by-products. It provides a systematic evaluation of different species groups and discusses various approaches for processing and fabricating repurposed collagen. This review specifically focuses on collagen-based research, encompassing an examination of its physical and chemical properties, as well as the potential for chemical modifications. We have detailed how the research and knowledge built on collagen structure and function will drive the new initiatives that will lead to the development of new products and opportunities in the future. Additionally, it highlights emerging approaches for extracting high-quality protein from waste and discusses efforts to fabricate collagen-based materials leading to the development of new and original products within the chemical, biomedical and physical science-based industries.


Assuntos
Colágeno , Resíduos , Colágeno/química , Colágeno/isolamento & purificação , Animais , Resíduos/análise
12.
BMC Biotechnol ; 24(1): 51, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090578

RESUMO

This study explores the potential antibacterial applications of zinc oxide nanoparticles (ZnO NPs) enhanced with silver (Ag) using plant gel (ZnO-AgO NPs). The problem addressed is the increasing prevalence of pathogenic bacteria and the need for new, effective antimicrobial agents. ZnO NPs possess distinctive physicochemical properties that enable them to selectively target bacterial cells. Their small size and high surface area-to-volume ratio allow efficient cellular uptake and interaction with bacterial cells. In this study, the average size of the synthesized ZnO-Ag nanoparticles was 77.1 nm, with a significant standard deviation of 33.7 nm, indicating a wide size distribution. The nanoparticles demonstrated remarkable antibacterial efficacy against gram-negative and gram-positive bacteria, with inhibition zones of 14.33 mm for E. coli and 15.66 mm for B. subtilis at a concentration of 300 µg/ml. Minimum inhibitory concentrations (MIC) were determined to be 100 µg/ml for E. coli and 75 µg/ml for S. saprophyticus. Additionally, ZnO-Ag NPs exhibited excellent biocompatibility, making them appropriate for various pharmacological uses. This study utilizes Ferula latisecta gels, offering a sustainable and eco-friendly approach to nanoparticle synthesis. Incorporating of Ag into ZnO NPs significantly enhances their antimicrobial properties, with the combined results showing great inhibition effects on pathogenic microbes. The findings suggest that ZnO-Ag NPs could be a promising candidate for addressing the challenges posed by drug-resistant bacterial infections and enhancing antimicrobial treatments.


Assuntos
Antibacterianos , Ferula , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Prata , Óxido de Zinco , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Prata/química , Prata/farmacologia , Nanopartículas Metálicas/química , Bactérias Gram-Positivas/efeitos dos fármacos , Óxido de Zinco/química , Óxido de Zinco/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Ferula/química , Géis/química , Géis/farmacologia , Escherichia coli/efeitos dos fármacos
13.
Gels ; 10(8)2024 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-39195062

RESUMO

In this study, novel functional ZEO-complex gels were prepared using sodium alginate, inulin, grape seed extract (GSE), and Zanthoxylum bungeanum essential oil (ZEO) as the primary raw materials. The effect of the addition of inulin, GSE, and ZEO on water vapor permeability (WVP), tensile strength (TS), and elongation at break (EAB) of ZEO-complex polysaccharide gels was investigated. A comprehensive score (Y) for evaluating the characteristics of ZEO-complex polysaccharide gels was established by principal component analysis. MATLAB analysis and box-Behnken design describe each factor's four-dimensional and three-dimensional interactions. It was found that Y could reach the maximum value when the ZEO addition was at a moderate level (C = 2%). The optimum preparation process of ZEO-complex polysaccharide gels was as follows: the addition of inulin was at 0.84%, the addition of GSE was at 0.04%, and the addition of ZEO was at 2.0785%; in this way, the Y of ZEO-complex polysaccharide gels reached the maximum (0.82276). Optical scanning and X-ray diffraction tests confirmed that the prepared ZEO-complex gels have a smooth and continuous microstructure, good water insulation, and mechanical properties. The storage test results show that ZEO-complex polysaccharide gels could play a significant role in the storage and fresh-keeping of grass carp, and the physicochemical properties of complex polysaccharide gels were improved by adding ZEO. In addition, according to the correlation of fish index changes during storage, adding ZEO in complex polysaccharide gels was closely correlated with the changes in fish TBARS and TVB-N oxidation decay indices. In conclusion, the ZEO-complex polysaccharide gels prepared in this study had excellent water insulation, mechanical properties, and outstanding fresh-keeping effects on grass carp.

14.
Macromol Rapid Commun ; : e2400419, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39116444

RESUMO

This study reports the reversible solubility switching of a polymer triggered by non-phototoxic visible light. A photochromic polymerizable azobenzene monomer with four methoxy groups at the ortho-position (mAzoA) was synthesized, exhibiting reversible photoisomerization between trans- and cis-states using green (546 nm) and blue light (436 nm). Free radical copolymerization of hydrophilic dimethylacrylamide (DMAAm) with mAzoA produced a light-responsive random copolymer (P(mAzoA-r-DMAAm)) that shows a reversible photochromic reaction to visible light. Optimizing mAzoA content resulted in P(mAzoA10.7-r-DMAAm)3.0 kDa exhibiting LCST-type phase separation in PBS (pH 7.4) with trans- and cis-states at 39.2 °C and 32.9 °C, respectively. The bistable temperature range of 6.3 °C covers 37 °C, suitable for mammalian cell culture. Reversible solubility changes were demonstrated under alternating green and blue light at 37 °C. 1H NMR indicated significant retardation of thermal relaxation from cis- to trans-states, preventing undesired thermal mechanical degradation. Madin Darby Canine Kidney (MDCK) cells adhered to the P(mAzoA-r-DMAAm) hydrogel, confirming its non-cytotoxicity and potential for biocompatible interfaces. This principle is useful for developing hydrogels that can reversibly stimulate cells mechanically or chemically in response to visible light.

15.
Heliyon ; 10(15): e35187, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39161809

RESUMO

Ionic conductive hydrogel has recently garnered significant research attention due to its potential applications in the field of wearable and flexible electronics. Nonetheless, the integration of multifunctional and synergistic advantages, including reliable electronic properties, high swelling capacity, exceptional mechanical characteristics, and self-adhesive properties, presents an ongoing challenge. In this study, we have developed an ionic conductive hydrogel through the co-polymerization of 4-Acryloylmorpholine (ACMO) and sodium acrylate using UV curing technology. The hydrogel exhibits excellent mechanical properties, high conductivity, superior swelling capacity, and remarkable self-adhesive attributes. The hydrogel serves as a highly sensitive strain sensor, enabling precise monitoring of both substantial and subtle human motions. Furthermore, the hydrogel demonstrates the capability to adhere to human skin, functioning as a human-machine interface for the detection of physiological signals, including electromyogram (EMG) signals, with low interfacial impedance. This work is anticipated to yield a new class of stretchable and conductive materials with diverse potential applications, ranging from flexible sensors and wearable bio-electronics to contributions in the field of artificial intelligence.

16.
ACS Appl Mater Interfaces ; 16(35): 46923-46936, 2024 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-39164962

RESUMO

3D printing ultralightweight porous structures using direct ink writing (DIW) while maintaining their mechanical robustness is highly challenging. This difficulty is amplified when low ink concentrations are used to create complex geometries. Herein, this shortfall was addressed by interfacially jammed emulsion gels. The gel emerged from the electrostatic interaction among synergized nanomaterials (graphene oxide (GO) and cellulose nanocrystals (CNCs)) in the aqueous phase and a ligand in the oil phase. This interaction led to the jamming of the nanoparticles and the creation of stable emulsion gels. The formed interfacial assemblies were further treated by post-jamming ionic cross-linking with NaHCO3, which dictated the emulsion gels' rheological characteristics, enhancing the ink's viscoelastic properties for high-resolution 3D printing. The customizable emulsion system allows control over porosity from the macro- to the micro-scale and generates complex geometries with desired compositions. By manipulating post-annealing processes and varying concentrations, it is possible to achieve aerogels that feature a remarkably low density (∼2.63 mg/cm3) and adjustable mechanical robustness (elastic modulus of 0.45 MPa). Additionally, this method allows for producing aerogels with flexible or stiff characteristics as required, alongside the capability to tailor specific electromagnetic shielding effectiveness (ranging from 6791 to 19615 dB cm2/g), showcasing the technique's versatility and engineerability.

17.
Food Res Int ; 192: 114759, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147534

RESUMO

To investigate the quality of different ozone-oxidized surimi gels and their in vitro digestion and absorption characteristics, surimi rinsed with different concentrations of ozonated water (0, 8, 26 mg/L) were prepared. Then, the degree of oxidation and gel structure of surimi were determined, the in vitro digestion and absorption of the gels were simulated, and the digestion and absorption products were analyzed by LC-MS/MS. The results showed that the quality of surimi gels was improved after proper ozone oxidation. After ozone water rinsing, the dry matter digestibility, peptide, and amino acid content increased, and the changes of all three were in line with the Logistic kinetic model (R2 = 0.95-0.99). Caco-2 cell absorption experiments showed that the absorption rate of peptides and amino acids decreased after ozone water rinsing. In summary, ozone oxidation can promote the digestion of surimi gels, but it also reduces the absorption of peptides and amino acids by Caco-2 cells. This study provides a reference for the application of ozone in the food field.


Assuntos
Carpas , Digestão , Produtos Pesqueiros , Oxirredução , Ozônio , Ozônio/química , Células CACO-2 , Animais , Humanos , Produtos Pesqueiros/análise , Carpas/metabolismo , Géis/química , Aminoácidos/metabolismo , Aminoácidos/análise , Espectrometria de Massas em Tandem , Absorção Intestinal , Peptídeos
18.
Food Res Int ; 192: 114764, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39147556

RESUMO

Protein emulsion gels, as potential novel application ingredients in the food industry, are very unstable in their formation. However, the incorporation of sour substances (phosphoric acid, lactic acid, acetic acid, malic acid, glutamic acid, tartaric acid and citric acid) would potentially contribute to the stable formation of whey protein isolate (WPI) emulsion as well as its gel. Thus, in this work, physical stability of seven acid-treated WPI emulsions, and microstructures, rheological properties, water distribution of its emulsion gels were characterized and compared. Initially, the absolute zeta-potential, interfacial protein adsorption, and emulsifying characteristics of acid-induced WPI emulsions were higher in contrast to acid-untreated WPI emulsions. Moreover, acid-induced WPI emulsions were thermally induced (95 ℃, 30 min) to form its emulsion gel networks via disulfide bonds as the main force (acid-untreated WPI emulsions were unable to form gels). High-resolution microscopic observation revealed that acid-induced WPI in emulsion gel network showed the morphology of aggregates. Dynamic oscillatory rheology results indicated that acid-induced emulsion gel exhibited highly elastic behavior and its viscoelasticity was associated with the generation of protein gel networks and aggregates. In addition, PCA and heatmap results further illustrated that malic acid-induced WPI emulsion gels had the best water holding capacity and gel characteristics. Therefore, this study could provide an effective way for the foodstuffs industry to open up new texture and healthy emulsion gels as fat replaces and loading systems of bioactive substances.


Assuntos
Emulsões , Géis , Temperatura Alta , Reologia , Proteínas do Soro do Leite , Proteínas do Soro do Leite/química , Emulsões/química , Géis/química , Viscosidade
19.
ACS Appl Mater Interfaces ; 16(32): 42049-42058, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39092793

RESUMO

Carbon black slurry electrodes are an effective means to improve flow battery performance by increasing the active surface area necessary for electrochemical reactions with a cost-effective material. Current challenges with this specific flow battery chemistry include the stability and flowability of the carbon black suspensions, especially in response to formulation choices. Advancing the manufacturing, operation, and performance of these redox flow batteries requires a deeper understanding of how slurry formulation impacts its rheological profile and ultimately battery performance. In response to this need, the linear and nonlinear rheological responses of activated carbon (AC) based slurry electrode materials used in an all-iron flow battery in the presence of a nonionic surfactant (Triton X-100) were measured. Results from these measurements show the slurry is a colloidal gel with elasticity remaining constant despite increasing surfactant concentration until α (= Csurf/CAC) < 0.65. However, at α ≥ 0.65, the slurry abruptly transitions to a fluid with no measurable yield stress. This critical surfactant concentration at which the rheological profile undergoes a dynamic change matches the concentration found previously for gel collapse of this system. Moreover, this transition is accompanied by a complete loss of electrical conductivity. From these data we conclude the site specific adsorption of surfactant molecules often used in slurry formulation has a significant and dramatic impact on the stability and flowability of these suspensions. Work presented herein demonstrates the importance of additive choices when formulating a slurry electrode.

20.
Angew Chem Int Ed Engl ; : e202414136, 2024 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-39161230

RESUMO

Responsive photonic crystals (RPCs) exhibit dynamic chromism upon trigger by various solvents, showing potential applications in qualitative identification and quantitative analysis of multicomponent solvents. However, distinguishing similar solvents, especially traces of cosolvents, remains challenging due to the limited sensitivity of RPCs. To address this, we herein introduce brush-like polymeric gels inside photonic crystals, forming a brush-like polymeric photonic gel (BPPG) that can trace tiny component changes. In this BPPG system, the acrylate backbones and PEG side-chains stretch incrementally due to the cosolvency of ethanol-water mixtures, resulting in highly sensitive chromatic responses within ethanol-rich concentrations. With water content varying slightly from 0 to 1 vol%, the reflection wavelength of BPPG can sharply redshift over 30 nm, leading to very noticeable changes in structural color. This enhanced sensitivity makes BPPG suitable for real-time, in-situ purity monitoring of absolute ethanol during storage, transportation, and other applications.

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