Gelatin Alginate Research Articles

Biomechanically inspired composite hydrogel bioink enhances engineered cartilage formation

Current therapies for articular cartilage defects or degeneration (osteoarthritis) remain unsatisfactory. There are significant clinical demands for the development of more efficient approaches to enhance the repair or regeneration of articular cartilage lesions. In this study, a newly defined alginate-gelatin (A-G) composite bioink was synthesized using the carbodiimide chemistry crosslinking method. Then, the dual-crosslinking (DC) bioscaffolds containing both chemical and ionic networks were fabricated by 3D-bioprinting technique and Ca2+ treatment. The optimized networks formed in the DC bioscaffolds provided a desirable Young’s modulus and geometric constraints, which were superior to that of the single-crosslinking (SC) control group to mimic the mechanical properties of the pericellular matrix (PCM) of native articular cartilage. Chondrocytes exhibited above 95% viability and higher proliferation rate in the 3D printed A-G-DC bioscaffolds than in the alginate-only group after 7 days in vitro culture. Chondrogenic differentiation in vitro was improved in the A-G-DC bioscaffolds than that of the alginate-only group, indexed by upregulation of chondrogenic marker gene expression including Sox9, Col2a1, Comp and Aggrecan. In the subcutaneous transplantation model and osteochondral defect model in mice with severe combined immunodeficiency (SCID), the A-G-DC bioscaffolds exhibited enhanced chondrogenesis and repair capacity than the alginate-only or none-implant control group, characterized by the increased expression of SOX9 and collagen type II (Col II) and higher ICRS II scores, respectively. These findings demonstrated that the biomechanically inspired A-G composite bioink and the 3D-printed A-G-DC bioscaffolds possess excellent cell biocompatibility, satisfactory biomechanical properties and chondrogenesis promotion capacity, which have the potential to be applied to enhance cartilage regeneration for patients with articular cartilage lesions.

Characterization of Biopolymer Hydrogels Prepared with Water Exposed to Indirect Plasma Treatment.

This study aimed to evaluate the influence of indirect-plasma-treated water (IPTW) in the preparation of hydrogels. Three commonly used natural, biodegradable polymers with the ability to form gels were selected: gelatin, carrageenan, and sodium alginate. The pH, gelling temperature, texture profile, swelling degree, and color of hydrogels were evaluated, and the polymers were subjected to Fourier-transform infrared (FTIR) spectroscopy. The morphology of the hydrogels was investigated using Scanning Electron Microscopy (SEM). Additionally, the physiochemical properties of the water media, which were distilled water (DW) and IPTW, were analyzed. The results indicated that the gels prepared using IPTW were characterized by a lower pH, higher hardness and lower gelation temperature. After 48 h of swelling ratio (SR) testing, gelatin and alginate hydrogels made with IPTW were characterized by lower SR, while an inverse relationship was found in the case of SR of carrageenan gels. The FTIR analysis confirmed changes in the water binding ability. The use of IPTW also significantly affected the microstructure of the tested materials. A statistically significant change in the color of IPTW gel samples was also noted. The results showed that IPTW induces physicochemical changes in hydrogels, which can lead to the enhancement of their practical applications.

Preparation and kinetic studies of a new antibacterial sodium alginate gelatin hydrogel composite.

This study involved synthesis of a novel antibacterial heterocyclic compound, sodium 2-(2-(3-phenyl-1, 2, 4-oxadiazol-5-yl) phenoxy) acetate abbreviated as Na-POPA. Further development of a biocompatible, pH-responsive hydrogel drug carrier prepared utilizing the natural polymers gelatin and sodium alginate. The compound loaded on the hydrogel represented new drug delivery system. Comprehensive characterization of Na-POPA was performed using Fourier-transform infrared spectroscopy (FT-IR), proton nuclear magnetic resonance (¹H NMR), carbon-13 nuclear magnetic resonance (¹³C NMR), and high-resolution mass spectrometry (HRMS). The compound was loaded onto the sodium alginate/gelatin hydrogel carrier under feasible experimental conditions. The successful incorporation of Na-POPA into the hydrogel matrix was confirmed via scanning electron microscopy (SEM), powder X-ray diffraction (pXRD) analysis and FT-IR spectroscopy. Cytotoxicity assays revealed that the all the loaded and unloaded compound induced cell toxicity at large concentration much lower than many reported results. The hydrogel reduced the inherent cytotoxicity of Na-POPA and enhanced its biocompatibility. The release kinetics of Na-POPA from the hydrogel were evaluated spectrophotometrically at different pH conditions simulating biological fluids. The release rate at pH 1.2 was greater than the release at pH 6.8, with a higher cumulative release observed at pH 6.8. The release kinetics obeyed the pseudo-second-order kinetic model, indicating a controlled release mechanism influenced by the hydrogel's physicochemical properties. Electrochemical impedance spectroscopy and cyclic voltammetry further confirmed that the compound release was pH-dependent. The high swelling and solubility at pH 6.8 enhance the release. The larger amount released at 6.8 (target intestine) because of more solubility, leaching and swelling rather than shrinking.

Development of modular extrusion bioprinter prototype

Introduction: The aim of this work was to develop a prototype of a modular extrusion bioprinter capable of performing 2D and 3D printing with hydrogels based on sodium alginate and gelatin. Materials and methods: The bioprinter uses Cartesian coordinate system, the print head is movable in Y and Z axes, the printing platform is in X axis and equipped with cooling system. Constructs were printed with 3 types of gels: based on gelatin with the addition various concentrations of xanthan gum; based on combination of gelatin and sodium alginate; based on gelatin and xanthan gum with the addition of carbon nanotubes. Results: The constructs from various gels corresponded to the structure determined by their digital models. Conclusions: The developed system allows performing 2D and 3D printing with gels based on gelatin, sodium alginate, including those containing carbon nanotubes and/or xanthan gum for a wide range of experimental tasks.

Constructing stable emulsion gel from gelatin and sodium alginate as pork fat substitute: Emphasis on lipid digestion in vitro

This study aimed to develop a gelatin-sodium alginate (G-SA) emulsion gel that can efficiently hold corn oil, as a substitute for pork fat while controlling the digestive behaviors of lipids in vitro. UV, fluorescence, and circular dichroism spectra and surface hydrophobicity measurements of the G-SA mixtures indicated that gelatin and sodium alginate primarily form aggregates through hydrogen bonds and hydrophobic interactions, and the optimum gelatin-to-sodium alginate w/w ratio was identified as 1.9. The final emulsion gel contained 3.15% gelatin and 1.65% sodium alginate (w/w) with a corn oil content of 40% (w/w). G-SA emulsion gel had a higher proportion of polyunsaturated fatty acids (PUFAs, 53.95 g/100 g) than pork fat (15.17 g/100 g). In addition, the G-SA emulsion gel exhibited stable viscoelastic properties without storage and loss moduli changes at increasing shear rates. The G-SA emulsion gel had a higher melting temperature (42.63 °C) than pork fat (35.07 °C). In vitro digestion studies showed that corn oil had a higher free fatty acid release (40.32%) compared to the G-SA emulsion gel (12.66%) and pork fat (8.53%) (P<0.05), indicating that the digestibility of corn oil was reduced in the G-SA emulsion gel. Calcein release experiments revealed that G-SA emulsion gel released the least amount of calcein (P<0.05) during digestion at a slow rate. The G-SA emulsion gel, similar to pork fat, contained evenly distributed digestive particles encapsulating corn oil after in vitro gastric digestion, with the smallest particle size among the treatments. After the in vitro small intestinal digestion phase, the G-SA emulsion gel maintained small droplet sizes with bridging flocculation. The in vitro digesta of the G-SA emulsion gel contained a significantly higher proportion of PUFAs compared to pork fat (P<0.05). Consequently, the G-SA emulsion gel can be a potential substitute for pork fat, offering higher proportions of PUFAs, lower fat content, and controlled lipid digestion with reduced lipid digestibility.

POM-Based Hydrogels for Efficient Synergistic Chemodynamic/Low-Temperature Photothermal Antibacterial Therapy.

Bacterial infection of wound surfaces has posed a significant threat to human health and represents a formidable challenge in the clinical treatment. In this study, a novel antimicrobial hydrogel utilizing POM is synthesized as the primary component, with gelatin and sodium alginate as the structural framework. The resultant hydrogel demonstrates exceptional mechanical properties and viscoelasticity attributed to the hydrogen-bonded cross-linking between POM and gelatin, as well as the ionic cross-linking between sodium alginate and Ca2+. In addition, the integration of CuS nanoparticles conferred photothermal properties to the hydrogel system. To address the concerns regarding the potential thermal damage to the surrounding normal cells, this study employs a LT-PTT combined with CDT approach to achieve the enhanced antimicrobial efficacy while minimizing the inadvertent harm to the healthy cells. The findings suggested that POM-based hydrogels, serving as an inorganic-organic hybrid material, will represent a promising antimicrobial solution and offer valuable insights for the development of the non-antibiotic materials.

Exploring the tunable micro-/macro-structure enabled by alginate-gelatin bioinks for tissue engineering

This study explores the development of optimized alginate-gelatin (AG) bioinks for advanced 3D bioprinting applications, particularly in tissue engineering. Central to our investigation is the establishment of a method for producing AG bioinks with highly tunable viscoelastic properties and the ability to create both macro- and micro-porous scaffolds through a liquid-liquid emulsion technique applied to chemically crosslinked hydrogels and shaped by microextrusion. Our methodology encompasses a comprehensive evaluation of homogenization, pasteurization techniques, and rheological assessments to optimize the mechanical properties of AG hydrogels, ensuring their suitability for bioprinting.The study demonstrates that dynamic homogenization and conventional pasteurization methods yield superior dissolution and sterility of the bioinks, crucial for maintaining optical quality and biological compatibility. Crosslinking optimization significantly enhanced the elasticity and reduced post-crosslinking shrinkage of the hydrogels, a key factor in achieving desired cell viability and function within the engineered tissues. The incorporation of porosity through a controlled liquid-liquid emulsion process was found to enhance cellular interactions and integration within the bioprinted constructs.Our findings confirm that the rheological properties of bioinks play a crucial role in determining bioprintability, with temperature modulation emerging as a key tool for tailoring these characteristics. The biocompatibility and functional performance of the AG hydrogels were validated through in vitro experiments, demonstrating promising cell viability and proliferation. This research lays the groundwork for the development of advanced bioinks capable of supporting complex tissue architectures in regenerative medicine and tissue engineering. By marrying the versatility of alginate and gelatin with innovative fabrication techniques, our study advances the frontier of 3D bioprinting, paving the way for the creation of biomimetic tissues with enhanced physiological relevance and therapeutic potential.

Effect of edible coating of gelatin-sodium alginate with the addition of green tea (Camellia sinensis) extract on the characteristics of star fruit (Averrhoa carambola L.) during storage.

Star fruit has a good nutritional value but was very easy to damage. Edible coating can be used to extend the shelf life of star fruit. Green tea had been added to improve the mechanical properties and functional value of edible coating. This study aimed to evaluate the application of edible coating gelatin-sodium alginate with the addition of green tea to the physicochemical and microbiological characteristics of star fruit. This research was conducted by making edible coating solutions from gelatin, sodium alginate, glycerol, and green tea of various concentrations (0%, 5%, 10%, and 15%). The coating solution was applied to star fruit and stored for 1, 6, and 13 days to determine the effect of coating on the physicochemical and microbiological properties of star fruit. The results showed that adding green tea was not significantly different from the color change of the coating solution. However, there was a change in viscosity and pH along with the concentration of green tea extract (p < 0.05). FTIR analyses indicated that an interaction existed between gelatin-sodium alginate and green tea extract. The addition of green tea to star fruit with an edible coating of gelatin and sodium alginate could prevent weight loss (25.84%), reduce respiration rate (11.035mg CO2/kg/h), maintain fruit anatomy, protect against color change, inhibit pH changes (4.22), total titrated acid (0.22%), increase vitamin C (244.55mg/g), and even reduce damage for up to 13 days of storage. This study indicates that edible coating with the addition of green tea might be effective to retain the quality and extend the storage life star fruit.

Fabrication of bacteriorhodopsin-embedded hydrogel construct for biocompatible photosensitive device

Bacteriorhodopsin (br) is a promising photosensitive material with applications in energy conversion, biosensors, and optoelectronic devices due to its bio-sourced origin and photoelectrical properties. Despite advancements in recent years, the integration of br-based devices necessitates the use of materials with little biocompatibility and fabrication techniques with restricted customizability, limiting potential applications such as optocontrol of cell behavior, implants with 3D patterning for retinal disease treatment, and light-sensitive cell robots. To solve this limitation, this study presents a novel approach by embedding br into a hydrogel matrix. It utilizes an extrusion-based and 3D bioprinting technique, showcasing its light-sensitive characteristics within a fully biocompatible construct. The hydrogel, comprising gelatin and sodium alginate, offers excellent printability for generating structured designs with versatile patterns. Photoelectrical properties of the fabricated br-embedded hydrogel construct, such as differential response, light intensity sensitivity, and br concentration sensitivity, are identified through electrochemical characterization. The temporal and spatial pattern recognition ability, based on the photoelectrical characteristics, is demonstrated through modulated light illumination and different patterns of printed hydrogel construct. Pattern recognition ability was then applied to reconstruct images containing different Latin letters. This research presents a novel method for the fabrication of patterned hydrogel constructs with high biocompatibility and distinctive light-responsive properties, expanding the potential applications of br in bio-related scenarios. &amp;nbsp;

DEVELOPMENT OF GELATIN-SODIUM ALGINATE MICROPARTICLES FOR ORAL INSULIN DELIVERY

Oral delivery of peptide drugs in the management of diabetes remained a major challenge among formulation scientists in the pharmaceutical industry. In this study, insulin-loaded microparticles for oral delivery were prepared with gelatin and sodium alginate and combined at different ratios using the double emulsion technique. The insulin-loaded microparticles (MPs) were evaluated for yield, and particle size, shape and thermal properties were determined. The in vitro release of insulin and blood glucose reduction after oral administration to diabetic rats were determined. The microparticles formed were spherical and pitted. The prepared insulin-loaded microparticles showed a lag phase before insulin release. The gelatin:sodium alginate (Na-Alg) ratio of 0:1 was the only formulation that released the most in vitro. The percentage blood glucose reduction for subcutaneously administered insulin was significantly greater than that for the formulation (p &lt; 0.05). The reduction effect observed after orally administered insulin-loaded MPs in batch with Na-Alg-gelatin (1:1) was observed after 9 h. However, this effect was like the effect observed in subcutaneously insulin solution. There was gradual release with a sustain effect of lower blood glucose level for a period of 24 h. These results are indicative of its effectiveness as an alternative for the delivery of insulin.

Highly biocompatible, antioxidant and antibacterial gelatin methacrylate/alginate - Tannin hydrogels for wound healing

Gelatin (Gel) hydrogels are widely utilized in various aspects of tissue engineering, such as wound repair, due to their abundance and biocompatibility. However, their low strength and limited functionality have constrained their development and scope of application. Tannic acid (TA), a naturally occurring polyphenol found in plants and fruits, has recently garnered interest as a crosslinking, anti-inflammatory, and antioxidant agent. In this study, we fabricated novel multifunctional gelatin methacrylate/alginate-tannin (GelMA/Alg-TA) hydrogels using chemical and physical crosslinking strategies with gelatin methacrylate (GelMA), alginate (Alg), and TA as the base materials. The GelMA/Alg-TA hydrogels maintained a stable three-dimensional porous structure with appropriate water content and exhibited excellent biocompatibility. Additionally, these hydrogels demonstrated significant antioxidant and antibacterial properties and substantially promoted wound healing in a mouse model of full-thickness skin defects by modulating inflammatory responses and enhancing granulation formation. Therefore, our study offers valuable insights into the design principles of novel multifunctional GelMA/Alg-TA hydrogels, highlighting their exceptional biocompatibility, antioxidant, and antibacterial properties. GelMA/Alg-TA hydrogels are promising candidates for wound healing applications.

Composite bioink incorporating cell-laden liver decellularized extracellular matrix for bioprinting of scaffolds for bone tissue engineering

The field of bone tissue engineering (BTE) has witnessed a revolutionary breakthrough with the advent of three-dimensional (3D) bioprinting technology, which is considered an ideal choice for constructing scaffolds for bone regeneration. The key to realizing scaffold biofunctions is the selection and design of an appropriate bioink, and existing bioinks have significant limitations. In this study, a composite bioink based on natural polymers (gelatin and alginate) and liver decellularized extracellular matrix (LdECM) was developed and used to fabricate scaffolds for BTE using 3D bioprinting. Through in vitro studies, the concentration of LdECM incorporated into the bioink was optimized to achieve printability and stability and to improve the proliferation and osteogenic differentiation of loaded rat bone mesenchymal stem cells (rBMSCs). Furthermore, in vivo experiments were conducted using a Sprague Dawley rat model of critical-sized calvarial defects. The proposed rBMSC-laden LdECM–gelatin–alginate scaffold, bioprinted layer-by-layer, was implanted in the rat calvarial defect and the development of new bone growth was studied for four weeks. The findings showed that the proposed bioactive scaffolds facilitated angiogenesis and osteogenesis at the defect site. The findings of this study suggest that the developed rBMSC-laden LdECM–gelatin–alginate bioink has great potential for clinical translation and application in solving bone regeneration problems.

Body temperature-triggered adhesive ionic conductive hydrogels for bioelectrical signal monitoring

Bioadhesive ion-conductive hydrogels are essential in bioelectrical signal monitoring. However, highly adhesive hydrogels may cause discomfort, such as skin redness and pain when peeled off, which hinders their application. Here, we design a body temperature-triggered adhesive ionic conductive hydrogel based on biocompatible polyacrylamide (PAAM), gelatin, and sodium alginate (SA). Due to the temperature sensitivity of gelatin, the adhesion of the developed PAAM/gelatin/SA (PGS) hydrogel is rapidly enhanced upon exposure to human body temperature, and it decreases quickly within a short period (10 s) after cooling, thus enabling painless removal. At the same time, the hydrogel exhibits a Young’s modulus (∼265 kPa) similar to that of skin tissue and achieves a conformal contact to the skin. Benefiting from the low electrode-epidermal impedance, the developed hydrogel has a decent signal-to-noise ratio of about 25 dB, allowing high-fidelity recording of various bioelectrical signals and accurate recognition of movements. The temperature-triggered adhesion-changing conductive hydrogel presented in this work shows great potential for biomedical applications.

Tough and self-adhesive zwitterionic hydrogels with mechano-responsive release of bFGF for tympanic membrane repair

The tympanic membrane (TM) is constantly in a state of vibrating. However, there is currently a lack of drug-delivery scaffolds suitable for the dynamic environment of TM perforation. In this study, a mechano-responsive tough hydrogel was developed. It consists of basic fibroblast growth factor (bFGF)-loaded sodium alginate (SA) microspheres, polysulfobetaine methacrylate (polySBMA), and gelatin methacrylate (GelMA). This hydrogel was designed to serve as a TM scaffold to promote perforation healing under dynamic conditions. bFGF was encapsulated in SA microspheres, which were then incorporated into polySBMA-GelMA hydrogels through photo-initiated free radical polymerization. The mechanical properties, tissue adhesiveness, swelling properties, and degradation of the hydrogels were evaluated before and after microsphere incorporation. It was observed that incorporating bFGF-loaded SA microspheres did not significantly impact the adhesion and degradation mechanisms of the hydrogel. The compressive strength and tensile strength of the microsphere-incorporated hydrogel were up to 6.6 MPa and 64.1 kPa, respectively, suitable for a TM scaffold. The release behavior of bFGF from the hydrogel could be controlled by vibration stimulation without significantly affecting the hydrogel's mechanical properties, indicating a mechano-responsive nature of the hydrogel. The in vitro cytotoxicity assay demonstrated that the hydrogels showed no cytotoxic effects. Moreover, cell culture assays demonstrated that vibration stimulation could enhance the release of bFGF, significantly promoting cell proliferation and migration. The results demonstrate the significant potential of the mechano-responsive hydrogel as a scaffold for repairing TM perforations.

Guar gum enhanced sustained release and therapy effects of tilmicosin-loaded sodium alginate gelatin nanogels against porcine pleuropneumonia

Actinobacillus pleuropneumoniae is an important pathogen of porcine pleuropneumonia, causing huge economic losses to the global pig industry. In order to effectively treat pleuropneumonia infections, a novel tilmicosin-loaded pH-responsive sodium alginate gelatin nanogels with excellent sustained-release was designed by modifying with guar gum (GG). The nanogels modified with GG had uniform size and smooth surface, and its drug loading capacity was 58.2 ± 1.3 %. The nanogels had good palatability and more excellent antibacterial activity compared to tilmicosin solution. Its release rate was faster at pH = 5.5 release medium than those at pH = 7.4 medium. Compared to tilmicosin sodium alginate gelatin nanogels and tilmicosin solution, the mean residence time (MRT) and area under the drug-time curve (AUC) of tilmicosin nanogels modified with GG was enhanced by 3.74 and 1.47, and 3.53 and 1.60 folds, respectively. The excellent sustained-release, pH responsiveness and enhanced absorption of tilmicosin nanogel modified with GG made it more effective in the treatment of infections than that of tilmicosin solution and tilmicosin nanogels.The GG modified tilmicosin nanogels might be an promising formulation for treatment of porcine pleuropneumonia.

Ferulic acid and human platelet lysate incorporated alginate dialdehyde‐gelatin 3D (bio)printable hydrogels with biological activity

AbstractThis study investigates the creation of multifunctional scaffolds based on alginate dialdehyde (ADA) and gelatin (GEL) incorporating ferulic acid (FA), a phytotherapeutic agent with diverse pharmacological properties, and human platelet lysate (HPL). The multimaterial hydrogels were characterized in terms of degradation/swelling behavior showing that HPL decelerates the degradation process of ADA‐GEL hydrogels in absence of FA. A FA release study confirmed that the presence of HPL does not affect the FA release ability of ADA‐GEL hydrogel. A trinitrobenzenesulfonic acid (TNBS) assay confirmed no influence of HPL on the Schiff's base formation. The addition of HPL was shown to lead to a decrease in stiffness, mechanical stability, and viscosity of ADA‐GEL‐HPL inks. This effect was also observed for ADA‐GEL‐HPL inks when investigating their three‐dimensional (3D) printing ability. Cytocompatibility tests and a 3D bioprinting study confirmed the beneficial impact of the addition of HPL on MC3T3‐E1 cells. Moreover, an antibacterial effect provided by the addition of FA was confirmed while the incorporation of HPL led to higher VEGF‐A expression by MC3T3‐E1 cells. Overall, the addition of HPL and FA to ADA‐GEL hydrogel results in a promising ink, which has potential for future biofabrication applications.

Silk Fibroin-Enriched Bioink Promotes Cell Proliferation in 3D-Bioprinted Constructs.

Three-dimensional (3D) bioprinting technology enables the controlled deposition of cells and biomaterials (i.e., bioink) to easily create complex 3D biological microenvironments. Silk fibroin (SF) has recently emerged as a compelling bioink component due to its advantageous mechanical and biological properties. This study reports on the development and optimization of a novel bioink for extrusion-based 3D bioprinting and compares different bioink formulations based on mixtures of alginate methacrylate (ALMA), gelatin and SF. The rheological parameters of the bioink were investigated to predict printability and stability, and the optimal concentration of SF was selected. The bioink containing a low amount of SF (0.002% w/V) was found to be the best formulation. Light-assisted gelation of ALMA was exploited to obtain the final hydrogel matrix. Rheological analyses showed that SF-enriched hydrogels exhibited greater elasticity than SF-free hydrogels and were more tolerant to temperature fluctuations. Finally, MG-63 cells were successfully bioprinted and their viability and proliferation over time were analyzed. The SF-enriched bioink represents an excellent biomaterial in terms of printability and allows high cell proliferation over a period of up to 3 weeks. These data confirm the possibility of using the selected formulation for the successful bioprinting of cells into extracellular matrix-like microenvironments.

Misleading Pore Size Measurements in Gelatin and Alginate Hydrogels Revealed by Confocal Microscopy.

It is a well-documented phenomenon that the porous structure of hydrogels observed with vacuum-based imaging techniques is generated during the freezing and drying process employed prior to observation. Nevertheless, vacuum-based techniques, such as scanning electron microscopy (SEM), are still being commonly used to measure pore sizes in hydrogels, which is often not representative of the actual pore size in hydrated conditions. The frequent underestimation of the impact of freezing and drying on hydrogel structures could stem from a lack of cross-fertilization between materials science and biomedical or food science communities, or from the simplicity and visually appealing nature of SEM imaging, which may lead to an overemphasis on its use. Our study provides a straightforward and impactful way of pinpointing this phenomenon exploiting two hydrogels ubiquitously applied in tissue engineering, including gelatin methacryloyl and alginate as proof-of-concept hydrogels. By comparing images of the samples in the native hydrated state, followed by freezing, freeze-drying, and rehydration using SEM and confocal microscopy, we highlight discrepancies between hydrogel pore sizes in the hydrated versus the dry state. To conclude, our study offers recommendations for researchers seeking insight in hydrogel properties and emphasizes key factors that require careful control when using SEM as a characterization tool.

The Demineralization Optimization for Chitosan Synthesis from Crab Shell Waste (Portunus pelagicus)

Chitosan, gelatin, albumin, and sodium alginate are examples of natural polymers that are often utilized as a basis material for polymeric nanoparticles. The deacetylation of chitin molecules produces the formation of chitosan. Chitin, protein, CaCO3, MgCO3, and astaxanthin pigment are all found in crab shells. Crab shell is an undervalued potential waste. Despite the fact that copious crab shell waste can be used to produce raw materials and industrial products. According to the findings of Mohadi et al (2014), chitosan was extracted with a yield of 70.71% and a deacetylation degree of 76.6%. Previous research on optimizing chitosan synthesis has involved changing the base reagent at the deacetylation stage. The results showed that a 50% concentration of KOH reagent produced the best chitosan properties. Another study on the synthesis of chitosan from crab shells got a yield of 70.4%, and the following analysis showed that this high yield is due to the amount of calcium. Therefore, demineralization in the synthesis of chitosan from crab shells must be optimized. The calcium content was measured after optimization with various solvent concentration variations. The best demineralization optimization results use 3 M hydrochloric acid with a decrease in calcium content of 97.75%.

Revolutionizing Wound Healing: The Rise of Electrospinning Nanofibers for Bioactive Dressings

A noticeable focus in recent years has been on creating bioactive dressings that are tailored to meet the requirements of wounds that are both acute and chronic. Because of these exceptional properties, electrospinning nanofibers stand out as a potential choice among the creative solutions being investigated. Among these are very high porosity and superior permeability to water and air, both of which are essential for promoting wound healing conditions. Moreover, these nanofibers’ ability to ward against foreign infections makes them an attractive option for improving wound care protocols. It is particularly notable because they closely mimic the extracellular matrix since this property can greatly enhance the efficacy of skin regeneration and wound healing processes. The present study aimed to explore the use of electrospinning nanofibers for bioactive dressings and wound healing. Extensive literature search was performed and relevant articles were collected from various databases like Google scholar, Taylor and Francis, Science direct, Springer, Embase, and Willey. Electrospinning nanofiber applications for the bioactive healing of wounds. The investigation begins with a comprehensive review of the wound healing procedure and the several electrospinning techniques used here. The many natural and synthetic polymers that are used to make electrospinning wound dressings are discussed in more detail. Prominent natural polymers, including hyaluronic acid, collagen, gelatin, silk fibroin, chitosan, and sodium alginate, are emphasized due to their special qualities and possible advantages in wound treatment. Furthermore, the paper explores the wide application of artificial polymers such as polyvinyl alcohol, polyvinyl chloride, polyethylene lactone, polylactide, and polyurethane, providing insight into their roles in the advancement of sophisticated wound dressings. In conclusion, the development of electrospinning technology offers promising prospects for creating improved wound care products and dressings that have the potential to completely transform the wound management industry.