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This study aimed to explore the effects of various lipids on the structure, cooking quality, and in vitro starch digestibility of extruded buckwheat noodles (EBNs) with and without 20% high-amylose corn starch (HACS). Fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction revealed that lauric acid bound more strongly to starch than did stearic acid and oleic acid, and the binding capacity of fatty acids with starch was stronger than that of glycerides. The presence of HACS during extrusion facilitated increased formation of starch-lipid complexes. Evaluations of cooking quality and digestion characteristics showed that EBNs containing 20% HACS and 0.5% glycerol monooleate demonstrated the lowest cooking loss (7.28%), and that with 20% HACS and 0.5% oleic acid displayed the lowest predicted glycemic index (pGI) (63.54) and highest resistant starch (RS) content (51.64%). However, excessive starch-lipid complexes were detrimental to EBNs cooking quality and the resistance of starch to digestive enzymes because of the damage to the continuity of the starch gel network. This study establishes a fundamental basis for the development of EBNs with superior cooking quality and a relatively lower GI.

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A lean meat batter system was mixed with four plant proteins at 3, 6, 9, and 12% (w/w): pea protein A (PA), pea protein B (PB), brown rice protein (BR) and faba bean protein (FB). Texture profile analysis (TPA) revealed that increasing plant protein levels hardened the hybrid meat batters, with PA and PB leading to the hardest gels. TPA results were supported by micrographs, demonstrating that the two pea proteins formed large aggregates, contributing to a firmer hybrid meat gel. Dynamic rheology showed that the incorporation of plant proteins lowered the storage modulus (G') during the heating stage (20 to 72°C), yet the 6% PA treatment produced a final G' (after cooling) closest to the control (CL). Nuclear Magnetic Resonance (NMR) T2 relaxometry also demonstrated that plant proteins reduced the water mobility in hybrid meat batters. Results were in line with the cooking loss, except for a higher cooking loss in the BR formulation compared to the CL. Color measurement showed that increasing plant protein levels led to darker and yellower meat batters; however, the effect on redness varied among treatments. Overall, the findings suggest that pea proteins have superior functionality and compatibility within a lean poultry meat protein system, compared to BR and FB tested here.

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Low-salt surimi production is crucial as it addresses health concerns related to sodium intake while maintaining the quality and shelf-life of seafood products. This research focused on optimizing the gelation conditions for silver carp surimi with the addition of psyllium husk powder at low salt concentrations (0.5% and 1%, w/w) to investigate the effects of psyllium husk powder concentration, temperature, and time on gel strength and water-holding capacity. The quality was assessed in terms of gel strength and water-holding capacity. Following a single-factor exploration, a three-level orthogonal experiment was designed to evaluate the influence of these three variables using a combined scoring system. Results indicated that psyllium husk powder levels between 0.1% and 0.3% (w/w) enhanced gel strength and water-holding capacity. The optimal conditions were identified as follows: 1% (w/w) NaCl with 0.2% (w/w) psyllium husk powder for 2.5 h at 35 °C, and 0.5% (w/w) NaCl with 0.3% (w/w) psyllium husk powder for 3 h at 35 °C. Texture profile analysis revealed that psyllium husk powder increased the hardness of the surimi gel, promoting myosin cross-linking and denser gel structure. Compared to traditional surimi gel, which relies on ionic bonds, the optimized gel showed higher levels of disulfide cross-linking and enhanced hydrophobic interactions, resulting in a stronger gel structure. Sensory evaluation suggested that surimi gels with psyllium husk powder were perceived as better than those without psyllium husk powder. The study concludes that selecting the appropriate psyllium husk powder quantity and thermal processing conditions based on salt concentration can significantly improve the quality of low-salt surimi gels. Error analysis using one-way ANOVA was performed on all experimental data and (p < 0.05) indicated the significant difference.

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To investigate the gelation process of direct ultra-high-temperature (UHT) milk, a pilot-scale steam infusion heat treatment was used to process milk samples over a wide temperature of 142-157 °C for 0.116-6 s, followed by storage at 4 °C, 25 °C, and 37 °C. The results of the physicochemical properties of milk showed that the particle sizes and plasmin activities of all milk samples increased during storage at 25 °C, but age gelation only occurred in three treated samples, 147 °C/6 s, 142 °C/6 s, and 142 °C/3 s, which all had lower plasmin activities. Furthermore, the properties of formed gels were further compared and analyzed by the measures of structure and intermolecular interaction. The results showed that the gel formed in the 147 °C/6 s-treated milk with a higher C* value had a denser network structure and higher gel strength, while the 142 °C/6 s-treated milk had the highest porosity. Furthermore, disulfide bonds were the largest contributor to the gel structure, and there were significant differences in disulfide bonds, hydrophobic interaction forces, hydrogen bonds, and electrostatic force among the gels. Our results showed that the occurrence of gel was not related to the thermal load, and the different direct UHT treatments produced different age gels in the milk.

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The "instant" quality of instant rice noodles is significantly affected by slow rehydration during cooking. This happens as a result of the native rice starch's low ability to gelatinize as well as the high shear and pressure utilized in industries during the widely used extrusion molding process. In order to address this issue, the rice flour was pretreated with mild steam (MS) technology. The results revealed that the rehydration qualities of the rice noodles that were extruded from the steam-treated flour significantly improved. There was a reduction of 25.5% in the rehydration time, from 443 to 330 s. The MS-treated rice starch's peak viscosity increased to 4503 from 4044 mPa/s. Decreases in gelatinization enthalpy (ΔH) and short-range ordering also suggest a reduction in difficulty in accomplishing starch gelatinization. Scanning electron microscopy studies showed particle aggregation increased as the treatment duration lasted longer. In conclusion, our findings indicate that we successfully addressed the issue of slow rehydration in instant rice noodles while presenting a novel approach for their manufacturing in the manufacturing sector.

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Today, a significant part of production wells' stock has a high water cut percentage of 90% and above. Obviously, for this reason, the need to develop new and improved existing technologies for water shut-off in wells increases every year. Physico-chemical methods of water shut-off are based on the application of special reagents and compositions that plug the pathways of water inflow to the well. Depending on the mechanism and specific features of water barrier formation, isolation methods are divided into selective and non-selective. This article investigates the possibility of using hydrolyzed polyacrylonitrile as a gel-forming and precipitation-forming reagent for water shut-off technologies in production wells. A surfactant-polymer composition for the isolation of water inflow in production wells in objects with high salinity in formation water, possessing physical and chemical selectivity and providing permeability reduction only in water-saturated intervals, is proposed. The developed composition is the invert emulsion, which makes it possible to carry out treatment at a distance from the well and solve the problem of possible premature gel formation directly in the wellbore. The lowest effective concentration of HPAN in an aqueous solution for use as a gel-forming and sedimentation reagent was determined experimentally (5.0 wt% and more). The interaction of the polymer solution with a chromium crosslinker allows obtaining structured gels in the whole volume of the system. The structure of the gels was evaluated using the Sydansk classifier with the assignment of a letter code from A to J. It was experimentally proved that the structure of the obtained gels depends on the temperature and content of the crosslinking agent in the system; the more crosslinking agent in the composition of the system, the stronger the structure of the resulting gel. The optimal ratio of polymer and crosslinking agent to obtain a strong gel was obtained, which amounted to 5:1 by weight of dry polymer powder. For the HPAN concentration of 5 wt% according to the Sydansk classifier, the gel structure had the code "H"-slightly deformable non-flowing gel. The dependence of the volume of gel sediment obtained because of the interaction with mineralized water on the polymer concentration was studied. It was proved that an increase in the concentration of hydrolyzed polyacrylonitrile in the solution, as well as an increase in the concentration of calcium ions in mineralized water, leads to a larger volume of the resulting gel or precipitate and to the strengthening of the gel structure. The results of rheological studies of the developed composition, as well as experiments on thermal stability, are presented. The results of filtration tests on bulk reservoir models demonstrated the selectivity of the developed composition. The obtained value of the residual resistance factor for the oil-saturated low-permeability model was 1.49 units; the value of the residual resistance factor for the water-saturated high-permeability model was 18.04 units. The ratio of the obtained values of the residual resistance factor, equal to 0.08 (much less than 1), can characterize the developed composition as a selective material for water shut-off in producing wells. Existing technologies for water shut-off based on HPAN do not allow for making a treatment at a distance from the well and require the use of technological solutions to prevent premature gel sedimentation in the well. The developed composition makes it possible to solve the problem of premature gelation. In addition, the composition can form a blocking screen in highly permeable water-saturated zones. The development can be useful for deposits with difficult conditions (high mineralization in reservoir waters, boreholes with a horizontal end, elevated temperatures up to 80 °C).

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Gallic acid (GA) and epigallocatechin gallate (EGCG), cooperated at varied ratios (1:0, 3:1, 1:1, 1:3, and 0:1), were employed to modify gel properties of calcium induced-whey protein emulsion gel. The effects of GA/EGCG on emulsion morphology, as well as gel properties and in vitro digestive behavior of the emulsion gels were investigated. Compared with emulsions without phenolics, GA/EGCG induced slightly smaller particle size and stronger electrostatic repulsion between emulsion droplets. Moreover, GA/EGCG, notably at a ratio of 3:1, promoted electrostatic and hydrophobic interactions between protein molecules and the formation of a compact and filamentous gel microstructure, resulting in a remarkable increment in the gel strength (up to 106 %). Furthermore, in vitro oral digestion, dynamic gastric digestion (using an artificial gastric digestive system, AGDS), and intestinal digestion of the emulsion gels were simulated. Particle size and protein hydrolysis results revealed that GA/EGCG was prone to weaken the physical disintegration of gels, reduce protein hydrolysis, and enhance the stability of emulsified oil droplets during dynamic gastric digestion. As a consequence, delayed release of oil droplets was observed in the gels and more free fatty acids were released in the intestinal digestion, particularly in the gel with GA/EGCG (3:1). These findings would provide novel strategies for application of phenolic compounds in developing protein gel-based delivery systems.

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Radiative cooling is a promising technology that offers benefits such as reducing cooling energy demand, mitigating climate change impacts, and contributing to sustainable development. However, previous radiative cooling technologies are unable to manage humidity, which is crucial and energy-intensive in many applications. Therefore, it is necessary to extend the capabilities of radiative coolers to include humidity control. Here, we demonstrate a fiber-encapsulated gel structure (FEGS) to realize simultaneous radiative cooling and humidity control. By employing a phase equilibrium-based strategy, the FEGS can control relative humidity to any value between 30 and 80%. The changes in temperature, thermal conductivity, and water content during the regeneration process of FEGS were studied. Field tests demonstrated that the FEGS can achieve 5 °C subambient temperature reduction under direct sunlight while maintaining the relative humidity at a controlled level of 58 ± 3% for a continuous period of 3 days. This work can potentially pave the way for the comanagement of temperature and humidity in a passive, low-cost, and scalable way.

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Drilling cuttings from the rock formation generated during the drilling process are generally smashed to fine particles through hydraulic cutting and grinding using a drilling tool, and then are mixed with the drilling fluid during circulation. However, some of these particles are too small and light to be effectively removed from the drilling fluid via solids-control equipment. These small and light solids are referred to as low gravity solids (LGSs). This work aimed to investigate the effect of LGSs on the performance of oil-based drilling fluid (OBDF), such as the rheological properties, high-temperature and high-pressure filtration loss, emulsion stability, and filter cake quality. The results show that when the content of LGSs reached or even exceeded the solid capacity limit of the OBDF, the rheological parameters including the plastic viscosity, gel strength, and thixotropy of OBDF increased significantly. Furthermore, the filtration of OBDF increases, the filter cake becomes thicker, the friction resistance becomes larger, and the stability of emulsion of OBDF also decreases significantly when the concentration of LGSs reached the solid capacity limit of OBDF (6-9 wt% commonly). It was also found that LGSs with a smaller particle size had a more pronounced negative impact on the drilling fluid performance. This work provides guidance for understanding the impact mechanism of LGSs on drilling fluid performance and regulating the performance of OBDF.

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In this work, the simulated gastrointestinal digestion of myofibrillar protein gels (MPGs) with anionic xanthan (XMP) and sodium alginate (SMP)/cationic chitosan (CSMP)/neutral curdlan (CMP) and konjac (KMP) was investigated to develop muscle-gelled foods with good qualities before and after eating. The results indicated that the neutral CMP and KMP groups had higher gel strength and protein digestibility than the CSMP group. Xanthan and sodium alginate facilitated myosin degradation in gastrointestinal digestion because of the weak wraps between protein and anionic polysaccharides, gaining plentiful peptides (1790 and 1692 respectively) with molecular weights below 2000 Da. Chitosan and neutral curdlan could improve the strength of MP gel but inhibited proteolysis and resulted in low contents of released amino acids via the strong cross-linked network blocking trypsin contact. This work provides a theoretical basis for developing low-fat meat products with good qualities and digestion behaviors by simply controlling the ionic types of polysaccharides.

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This study aimed to explore new techniques to regulate the quality of soy products. The glucono-δ-lactone (GDL) induced soymilk gelation process and the gel network structure characteristic were compared as a matter of temperature, and the role of reaction kinetics was discussed. Results showed that there were similarities in the development of G' curves under different temperatures, whereas the gel network structures and the energy requirements of cross-linking reactions were different. In the high-temperature region (70 °C-95 °C), the exposure and binding of reactive groups were promoted. The activation enthalpy (ΔH*) required by protein aggregates decreased and the effect of entropy reduction (-TΔS*) was enhanced, which led to shorten the preaggregation time (tg) and increase the gelation rate (k), resulting in the formation of rough, porous gel network with high stiffness. By contrast, in the low-temperature region (40 °C-70 °C), high enthalpy contributions and low entropy changes were required, then a fine, soft, and tender gel network formed. Besides, a funnel-shaped model of the enthalpy-entropy energy transformation mechanism of soymilk gelation was proposed. The results of this study revealed that adjusting the enthalpy-entropy energy requirements of the protein cross-linking reaction could be utilized to the regulation of the network structure and quality of soymilk gels, which could enrich the reaction kinetics theory and provide innovative ideas for food quality control technology from the perspective of energy requirement and energy input.

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In this study, we evaluated the impact of Lactiplantibacillus plantarum (L. plantarum) with ropy and non-ropy phenotypes on gel structure and protein conformation of fermented milk. Ropy L. plantarum (T1 & CL80) secreted EPS with high molecular weight (1.41 × 106, 1.19 × 106 Da) and intrinsic viscosity (486.46, 316.32 mL/g), effectively enhances fermented milk viscosity and water holding capacity (WHC) (65.4%, 84.6%) by forming a dense gel structure. Non-ropy L. plantarum (CSK & S-1A) fermented milk gel's high surface hydrophobicity and free sulfhydryl content caused high hardness and low WHC. Raman spectroscopy combined with circular dichroism analysis showed that high levels of α-helix (29.32-30.31%) and random roil (23.06-25.36%) protein structures are the intrinsic factors that contribute to the difference among fermented milk gels of ropy and non-ropy strains. This study provides a basis for understanding the structural variability of fermented milk gels using ropy or non-ropy lactic acid bacteria.

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In this study, emulsion gels were constructed by ionic gelation method using egg yolk granules/sodium alginate bilayers emulsion. In particular, the main driving force of the emulsion gels was controlled by adjusting pH. Compared with pH 7.0, the mechanical properties of EYGs emulsion gel were enhanced at pH 4.0 (G' > G″). The interfacial protein aggregation that occurred at pH 4.0 promoted the compactness of the EYGs emulsion gel structure along with enhanced capillary effect. The emulsion gel structure tended to be complete at 1 % SA of pH 4.0, for the electrostatic interaction required more SA molecules involved in maintaining emulsion gel structural stability. The denser emulsion gel structure of pH 4.0 than pH 7.0 improved storage stability, FFA releasing, and chemical stability of ß-carotenes. Bioaccessibility of ß-carotenes also decreased to achieve sustained release. This study provides a theoretical basis for tuning emulsion gel structure to adjust encapsulation stability and in vitro digestion characteristics of active ingredients.

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Soybean protein isolate (SPI), as a full-valued protein, is rich in nutrients, such as amino acids. However, the isolated structure of soybeans makes it difficult to react and thus prepare good gels. In order to further improve the properties of SPIs and to prepare plant-based gels with good performance, this experiment was conducted to prepare maltodextrin glycosylated soybean isolate (MGSI) by the glycosylation of SPI and maltodextrin (MD), and the gels were prepared by thermal induction, transglutaminase (TGase) induction, and TG-MgCl2 co-induction of this glycosylated protein to investigate the effects of different induction methods on the structure and properties of the gels produced by MGSIs. Moreover, the effects of different induction methods on the structure and properties of the gels produced by MGSI were investigated. SDS-PAGE protein electrophoresis, FTIR spectroscopy, and endogenous fluorescence spectroscopy revealed that all three inductions result in the covalent bond cross-linking of MGSI during the gel formation process. Compared with thermal induction, the TGase-induced MGSI secondary structure had a higher content of ß-folded structures, increased fluorescence intensity of tertiary structures, and produced a red shift. The gel induced by TGase in collaboration with MgCl2 contains a more ß-folded structure and irregular curl and increases the ß-turned angle and α-helix content further, the endogenous fluorescence λmax is significantly red-shifted, and the fluorescence intensity increases, demonstrating that the tertiary structure of MGSI unfolds the most, forming multilayered gels with the tightest structures. The three gels were analyzed by rheology and SEM, showing that the TGase-MgCl2 synergistically induced gel had the highest energy-storage modulus G', viscoelasticity, and water-holding capacity, as well as the densest gel structure. In conclusion, the combined treatment of enzyme and MgCl2 might be an effective way of improving the structure and gel properties of SPI. This study helps to promote the high-value utilization of SPI and the development of plant protein gels.

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Reconstituted gluten fractions (RGF) varying in glutenin/gliadin (glu/gli) ratios was applied to change the property of wheat starch. The addition of RGF, irrespective of glu/gli ratio, significantly decreased the gelatinization enthalpy, viscosity, storage modulus (G'), and gel strength of starch. Starch particle size and leached amylose decreased by 4.5% and 22.2%, respectively, as the ratio of glu/gli changed from 1:0 to 0:1, indicating that the increase in gliadin ratio could inhibit swelling and rupturing of starch granules to a larger extent. Confocal laser scanning micrographs showed that gliadin could surround starch granules more effectively, thereby stabilizing the granule structure better than glutenin. With the increasing of gliadin ratio, the storage modulus (G') and loss modulus (G″) of the starch paste declined, accompanied by more loose gel structure and weaker gel strength. By varying the ratios of glu/gli in RGF, the change of wheat starch granule structure could be modulated, and therefore the rheological properties and gel structure could be regulated.

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The present study aimed to investigate the thermal- and pH-dependent gelation behavior of gelatin/HPMCP blends using ultraviolet (UV) spectrophotometry, viscoelasticity, and dynamic light scattering (DLS). We found that the release of lisinopril from gelatin/HPMCP gels can be inhibited at low pH. UV spectrophotometric analysis showed that pH had a significant effect on the transparency of aqueous HPMCP systems and gelatin/HPMCP gels. The viscoelastic patterns of gelatin/HPMCP at pH 4.6 considerably differed from those of gelatin/HPMCP at pH 5.2 and 6.0. DLS measurements showed that HPMCP molecules in low concentrations underwent strong aggregation below pH 4.8. Such HPMCP aggregation induces a physical barrier in the matrix structures of the gelatin/HPMCP gels, which inhibits the drug release at pH 1.2. This hydrogel delivery system using polymer blends of gelatin/HPMCP can be used in oral gel formulations with pH-responsive properties.

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The effect of the pulsed-vacuum stimulation (PVS) on the external gelation process of calcium-alginate (Ca-Alg) hydrogel balls was studied. The process was conducted at four different working pressures (8, 35, 61, and 101 kPa) for three pulsed-vacuum cycles (one cycle consisted of three repetitions of 10 min of depressurization and 10 min of vacuum liberation). The diffusion coefficients (D) of calcium cations (Ca2+) gradually reduced over time and were significantly pronounced (p < 0.05) at the first three hours of the external gelation process. The rate of weight reduction (WR) and rate of volume shrinkage (Sv) varied directly according to the D value of Ca2+. A significant linear relationship between WR and Sv was observed for all working pressures (R2 > 0.91). An application of a pulsed vacuum at 8 kPa led to the highest weight reduction and shrinkage of Ca-Alg hydrogel samples compared to other working pressures, while 61 kPa seemed to be the best condition. Although all textural characteristics (hardness, breaking deformation, Young's modulus, and rupture strength) did not directly variate by the level of working pressures, they were likely correlated with the levels of WR and Sv. Scanning electron micrographs (SEM) supported that the working pressure affected the characteristics of Ca-Alg hydrogel structure. Samples stimulated at a working pressure of 8 kPa showed higher deformation with heterogenous structure, large cavities, and looser layer when compared with those at 61 kPa. These results indicate the PVS is a promising technology that can be effectively applied in the external gelation process of Ca-Alg gel.

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A novel protein-based gel named "Yu dong" prepared with fish (Cyprinus carpio L.) scale aqueous extract and enhanced by polysaccharides is described in this study. The effects of pectin, alginate, and sodium carboxyl methyl cellulose (CMC-Na) on FS gel formation, stability, textural characteristics, microstructure, and water distribution were evaluated. The results indicated the viscosity of the FS gels decreased and changed slowly as the addition of pectin. While, the addition of alginate enhanced the formation of FS gels. As pectin addition in FS gels, the transition temperature decreased. When alginate and CMC-Na was added to the FS gels, the transition temperature increased. The addition of pectin, alginate, and CMC-Na to the FS gels significantly increased Gr from 44.5% to 71.99%, 61.86%, and 71.35%, respectively. Gel strength increased significantly as the addition of pectin, alginate, and CMC-Na. LF-NMR results showed that a moderate amount (0.2%) of polysaccharides bonded the protein and water more tightly, which was consistent with the SEM results showing gel structure with more uniform pores. This study provides a direct application of FS protein in preparing of gel food, which showing a better way to utilize the abandoned fish resource.

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Among available structuring agents that have been used to provide solid properties to liquid oils, protein is a more recent candidate. Due to their nutritional value and high consumer acceptance, proteins are of special interest for the preparation of edible oleogels as an alternative for solid fats. Whereas the field of protein oleogelation is still rather new and just starts unfolding, several preparation methods have been demonstrated to be suitable for protein oleogel preparation. However, there is limited knowledge regarding the link between microstructural properties of the gels and macroscopic rheological properties, and the potential of such protein-based oleogels as a fat replacer in food products. In this review, we therefore provide an overview of various protein oleogel preparation methods and the resulting gel microstructures. Based on the different structures, we discuss how the rheological properties can be modified for the different types of protein oleogels. Finally, we consider the suitability of the different preparation methods regarding potential applications on industrial scale, and provide a short summary of the current state of knowledge regarding the behavior of protein oleogels as a fat replacer in food products.

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Structural and compositional similarity to the natural extracellular matrix (ECM) is a main characteristic of an ideal scaffold for tissue regeneration. In order to resemble the fibrous/gel structure of skin ECM, a multicomponent scaffold was fabricated using biopolymers with structural similarity to ECM and wound healing properties i.e., chitosan (CS), gelatin (Gel) and hyaluronic acid (HA). The CS-Gel and CS-HA nanofibers were simultaneously electrospun on the collector through dual-electrospinning technique. The presence of polymers, possible interactions, and formation of polyelectrolyte complex were proven by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and thermogravimetric analysis (TGA). The noncomplex component of CS-HA fibers formed a gel state when the scaffold was exposed to the aqueous media, while the CS-Gel fibers reserved their fibrous structure, resulting in formation of fibrous/gel structure. The CS-Gel/CS-HA scaffold showed significantly higher cell proliferation (109%) in the first 24 h comparing with CS (90%) and CS-Gel (96%) scaffolds. Additionally, the initial cell adhesion improved by incorporation of HA. The in-vivo wound healing results in rat elucidated more wound healing capability of the CS-Gel/CS-HA scaffold in which new tissue with most similarity to the normal skin was formed.

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