Elastic Hydrogel Research Articles

Bioprinting a resilient and transparent cornea stroma equivalent: harnessing dual crosslinking strategy with decellularized cornea matrix and silk fibroin hybrid.

Bioprinting a resilient yet optically transparent corneal tissue substitute remains a challenge. In this study we introduce an innovative methodology aimed at bolstering the mechanical and optical attributes of silk fibroin (SF) hydrogels, pivotal for the progression of cornea tissue engineering. We devised a unique eosin Y-based photoinitiator system to instigate di-tyrosine linkages within highly concentrated pristine SF solutions under green light exposure. This pioneering technique resulted in SF hydrogels fortified by dityrosine covalent bonds, preserving exceptional transparency and soft elastomeric qualities devoid of spontaneous transitions to stiff, opaque beta-sheet conformations. Furthermore, we synergistically combined SF with decellularized corneal matrix (DCM) hydrogel, leveraging photo-polymerization under green light followed by thermal gelation to establish resilient and stable gel formation. The ensuing dual crosslinked hybrid hydrogels exhibited superior mechanical and thermal resilience in comparison to dual crosslinked DCM hydrogels. The inclusion of SF in DCM further augmented the hydrogel's elasticity and shear recovery, positioning it as an optimal bioink for cornea bioprinting endeavors. During the extrusion printing process, photocrosslinking of the bioink superficially fortified SF and DCM polymer chains via di-tyrosine linkages, furnishing initial stability and mechanical fortitude. Subsequent post-printing thermal gelation further reinforced collagen chains through self-assembly. Notably, the bioprinted cornea constructs, housing human limbal mesenchymal stem cells (hLMSCs), manifested transparency, structural integrity, and optimal functionality, underscored by the expression of keratocyte proteoglycans. In summation, our engineered 3D constructs exhibit promising potential for in vivo applications in cornea tissue engineering, marking a significant stride forward in the field's advancement.

Viscoelastic High-Molecular-Weight Hyaluronic Acid Hydrogels Support Rapid Glioblastoma Cell Invasion with Leader-Follower Dynamics.

Hyaluronic acid (HA), the primary component of brain extracellular matrix, is increasingly used to model neuropathological processes, including glioblastoma (GBM) tumor invasion. While elastic hydrogels based on crosslinked low-molecular-weight (LMW) HA are widely exploited for this purpose and have proven valuable for discovery and screening, brain tissue is both viscoelastic and rich in high-MW (HMW) HA, and it remains unclear how these differences influence invasion. To address this question, hydrogels comprised of either HMW (1.5 MDa) or LMW (60 kDa) HA are introduced, characterized, and applied in GBM invasion studies. Unlike LMW HA hydrogels, HMW HA hydrogels relax stresses quickly, to a similar extent as brain tissue, and to a greater extent than many conventional HA-based scaffolds. GBM cells implanted within HMW HA hydrogels invade much more rapidly than in their LMW HA counterparts and exhibit distinct leader-follower dynamics. Leader cells adopt dendritic morphologies similar to invasive GBM cells observed in vivo. Transcriptomic, pharmacologic, and imaging studies suggest that leader cells exploit hyaluronidase, an enzyme strongly enriched in human GBMs, to prime a path for followers. This study offers new insight into how HA viscoelastic properties drive invasion and argues for the use of highly stress-relaxing materials to model GBM.

High Ion-Conductive Hydrogel: Soft, Elastic, with Wide Humidity Tolerance and Long-Term Stability.

Ion-conductive hydrogels have received great attention due to their significant potential in flexible electronics. However, achieving hydrogels that simultaneously possess high ionic conductivity and stability under varying humidity conditions remains a challenge, limiting their practical applications. Herein, we propose a thermally controlled chemical cross-linking strategy to prepare an elastic and conductive hydrogel (ECH) of poly(vinyl alcohol) (PVA) with high content of H2SO4. The covalent cross-links formed effectively tackle the instability issue in high humidity of physically cross-linked PVA/H2SO4 hydrogels with high ionic conductivity, which were previously developed via the polymer-in-salt strategy. We systematically investigated the reaction conditions and clarified the methods to optimize the hydroxyl dehydration of PVA, resulting in excellent mechanical properties and ion conductivity simultaneously. The ECH demonstrates impressive ionic conductivity (up to 392 ± 49 mS cm-1) and elasticity (over 80% resilience upon stretching and compression after being equilibrated at various humidity levels for 24 days). Thanks to the excellent water retention of the high H2SO4 content, the ECH maintains an ionic conductivity exceeding 210 mS cm-1 for over 420 days at 50% relative humidity (RH) and retains over 100 mS cm-1 even after 3 days under extremely dry conditions (7% RH). These remarkable properties make the ECH an ideal candidate for applications requiring reliable ionic conductivity in diverse environmental conditions. Additionally, we demonstrated that the ECH can function as a stretchable Joule heater with high conformability for heating up objects with curved surfaces. The heating rate could reach a fast rate of ∼12 °C s-1 even when a human-safe alternating current voltage is below 36 V, attributed to the high ionic conductivity. We believe that the high performance and ease of fabrication make our hydrogels a promising candidate for use as electrolytes in flexible energy storage devices, electrolyte gates in electrochemical transistors, and artificial skin, which often face long-term stability challenges under varying humidity conditions.

Highly Stretchable Sensitive Multiscale Hydrogel Inspired by Biological Muscles for Wearing Sensors.

Hydrogels have attracted substantial research interest for application in wearable electronics due to their stretchability, elasticity, and compliance. However, most hydrogels could not satisfy the application requirements for high-performance wearable sensors due to their poor sensitivity, low mechanical properties, and sensing detection range until this day. Inspired by the fascia in biological muscles, we propose a strategy to form entangled "clusters" through the dense entanglement between highly cross-linked elastic hydrogel microspheres and polymer segments, and prepared a multiscale hydrogel with high sensitivity and mechanical toughness. This strategy embedded highly swollen hydrogel microspheres (with different pore sizes) to act as the microregions of dense entanglement in the soft matrix to adjust the microstructure of multiscale gel. When pressure was applied, this structure could provide a fast response due to the stack layer formed by microspheres and soft matrix produced effective stress distribution, resulting in the outstanding sensitivity of the multiscale hydrogel (S = 1.1 kPa-1) in the pressure range of 0-50 kPa. The distinct microspheres functioning as microscale joint areas significantly augment energy dissipation, culminating in exceptional mechanical stability, ultrastretchability (≈1050%), and high strength of the multiscale hydrogel. The most notable progress was that the synthesized multiscale hydrogel not only combined the above advantages but also simultaneously solved multiple dilemmas of tedious synthesis steps, high cost, and poor durability. Besides, the multiscale hydrogel also had excellent antibacterial properties and biocompatibility, which enabled them to have large-scale application potential in wearable and implantable electronic devices. Our research could provide a universal approach to the creation of robust, flexible, wearable, and sensitive sensors, significantly increasing the uses of stress sensors in wearable technology.

A highly elastic, moisturizing, and adhesion conductive hydrogel designed for cuffless blood pressure measurement

Real-time monitoring of blood pressure in athletes during exercise is of great importance, however, conventional methods pose challenges in achieving portable and instantaneous measurements. While, the electrodes used in emerging wearable blood pressure monitoring instruments still have certain defects. In this study, a novel cuffless blood pressure monitoring system was developed using a self-developed polyacrylamide/trehalose/LiCl (PAM/Trehalose/LiCl) conductive hydrogel as the electrode material. The hydrogel electrode has high tensile (strain: 3568 %) and conductive properties (7.57 S/m), while also exhibiting low toughness, moisture retention, and adhesion. While ensuring the comfort of the monitoring system, it can also accurately detect strain over a wide range of deformations (GF value of up to 6.31 in the strain interval of 2000–3400 %). Finally, this system accurately extracts relevant features of PPG and ECG signals and predicts cuff-less blood pressure using the BP Transformer-XL model. The main control chip, ECG detection module, Bluetooth module, and PPG detection module are integrated, and band-pass filtering and data feature extraction techniques are combined. The study found that the average errors in systolic and diastolic readings were 2.09 mmHg and 1.57 mmHg, respectively, compared to those measured by an electronic sphygmomanometer. Therefore, this study successfully combined hydrogel electrodes with a cuffless blood pressure monitoring system to provide technical support for the development of personalized training programs for future athletes and the guarantee of long-term competitive performance.

Oxidization and Salting Out Synergistically Induced Highly Elastic, Conductive, and Sensitive Polyvinyl Alcohol Hydrogels

Oxidization and Salting Out Synergistically Induced Highly Elastic, Conductive, and Sensitive Polyvinyl Alcohol Hydrogels

Dual cross-linked polyurethane-alginate biomimetic hydrogel for elastic gradient simulation in osteochondral structures: Microenvironment modulation and tissue regeneration

The distinctive composition and functions of osteochondral structures result in constrained regeneration. Insufficient healing processes may precipitate the emergence of tissue growth disorders or excessive subchondral bone formation, which can culminate in the deterioration and failure of osteochondral tissue repair. To overcome these limitations, materials designed for osteochondral repair must provide region-specific modulation of the microenvironment and mechanical compatibility. To address these challenges, we propose a method to create continuous hydrogels with distinct structural and functional properties by a precise cross-linking method. We have developed an innovative polyurethane enriched with dimethylglyoxime, facilitating the coordinated loading and precise release of Zn2+. This strategy enables the meticulous control of alginate cross-linking, resulting in an elastic gradient hydrogel that closely resembles the osteochondral interface. The SeSe within the hydrogel effectively modulates the inflammatory microenvironment and fosters the M2 polarization of macrophages. The hydrogel's lower layer is designed to rapidly release Zn2+, thereby enhancing bone regeneration. The upper layer is intended to prevent bone overgrowth and stimulate chondrogenic differentiation. This dual-layer strategy allows targeted stimuli to each region, promoting the seamless integration of neoosteochondral tissue. Our study demonstrates the potential of this stratified hydrogel in achieving uniform and smooth osteochondral tissue regeneration.

Engineering living root with mechanical stimulation derived from reciprocating compression in a double network hydrogel as elastic soil

The root system actively reacts to mechanical stimuli in its environment, transmitting mechanical signals to optimize the utilization of environmental resources. While the mechanical impedance created by the growth medium serves as the primary source of stimulation for the roots, extensive research has focused on the roots' response to static mechanical stimulation. However, the impact of dynamic mechanical stimulation on root phenotype remains underexplored. In this study, we utilized a low acyl gellan gum/polyacrylamide (GG/PAM) double network elastic hydrogel as the growth medium for rapeseed. We constructed a mechanical device to investigate the effects of reciprocating extrusion stimulation on the growth of the rapeseed root system. After three weeks of mechanical stimulation, the root system exhibited a significant increase in lateral roots. This branching enhanced the roots' anchoring and penetration into the hydrogel, thereby improving the root system's adaptability to its environment. Our findings offer valuable data and insights into the effects of reciprocating mechanical stimulation on root growth, providing a new way for engineering root phenotype.

Detection of Sulfonamide Antibiotics Using an Elastic Hydrogel Microparticles-Based Optical Biosensor.

Sulfonamide antibiotics were the first synthetic antibiotics on the market and still have a broad field of application. Their extensive usage, wrong disposal, and limited degradation technologies in wastewater treatment plants lead to high concentrations in the environment, resulting in a negative impact on ecosystems and an acceleration of antibiotic resistance. Although lab-based analytical methods allow for sulfonamide detection, comprehensive monitoring is hampered by the nonavailability of on-site, inexpensive sensing technologies. In this work, we exploit functionalized elastic hydrogel microparticles and their ability to easily deform upon specific binding with enzyme-coated surfaces to establish the groundwork of a biosensing assay for the fast and straightforward detection of sulfonamide antibiotics. The detection assay is based on sulfamethoxazole-functionalized hydrogel microparticles as sensor probes and the biomimetic interaction of sulfonamide analytes with their natural target enzyme, dihydropteroate synthase (DHPS). DHPS from S. pneumoniae was recombinantly produced by E. coli and covalently coupled on a glass biochip using a reactive maleic anhydride copolymer coating. Monodisperse poly(ethylene glycol) hydrogel microparticles of 50 μm in diameter were synthesized within a microfluidic setup, followed by the oriented coupling of a sulfamethoxazole derivative to the microparticle surface. In proof-of-concept experiments, sulfamethoxazole, as the most used sulfonamide antibiotic in medical applications, was demonstrated to be specifically detectable above a concentration of 10 μM. With its straightforward detection principle, this assay has the potential to be used for point-of-use monitoring of sulfonamide antibiotic contaminants in the environment.

Nanocellulose/Selenoglutathione-Enhanced Antioxidant, Elastic, Antibacterial, and Conductive Hydrogels as Strain Sensors

Nanocellulose/Selenoglutathione-Enhanced Antioxidant, Elastic, Antibacterial, and Conductive Hydrogels as Strain Sensors

Design and molecular dynamics of biocompatible WPU/PVA composite hydrogels with enhanced fatigue resistance: Energy dissipation of intermolecular clusters for elastomers

To engineer a hydrogel elastomer for use as an in vivo tissue replacement, it is imperative to ensure superior fatigue resistance, guaranteeing a prolonged service life. Investigating the molecular mechanisms of strain energy accumulation and transmission, which occur during the compression of elastomeric materials, is instrumental in elucidating the causes of hydrogel material fatigue. Such insights are of immense value for the development of durable artificial tissue replacements, ensuring their longevity and sustained functionality within the human body. We synthesized hydrogel elastomers through polyvinyl alcohol (PVA) and waterborne polyurethane (WPU) with good biocompatibility, and studied their fatigue behavior through molecular dynamics (MD). The results of this analysis demonstrate that the introduction of energy dissipation structures between mechanically supported molecular frameworks can enhance the relaxation efficiency of polymers. This improvement leads to enhanced resistance of hydrogels to compression fatigue. A total of 1,000,000 cycles of compression tests were conducted to verify that WPU/PVA did not exhibit any significant compression fatigue under high stress of 50 % strain. In contrast, PVA hydrogel exhibited obvious fatigue due to the absence of an energy dissipation structure. These results revealed the source of compression fatigue resistance of hydrogel elasticity and provided powerful guidance for the design and synthesis of artificial tissues.

Injectable Dual Fenton/Enzymatically Cross-Linked Double-Network Hydrogels Based on Acrylic/Phenolic Polymers with Highly Reinforced and Tunable Mechanical Properties.

Injectable hydrogels have been extensively used as promising therapeutic scaffolds for a wide range of biomedical applications, such as tissue regeneration and drug delivery. However, their low fracture toughness and brittleness often limit their scope of application. Double-network (DN) hydrogel, which is composed of independently cross-linked rigid and ductile polymer networks, has been proposed as an alternative technique to compensate for the weak mechanical properties of hydrogels. Nevertheless, some challenges still remain, such as the complicated and time-consuming process for DN formation, and the difficulty in controlling the mechanical properties of DN hydrogels. In this study, we introduce a simple, rapid, and controllable method to prepare in situ cross-linkable injectable DN hydrogels composed of acrylamide (AAm) and 4-arm-PPO-PEO-tyramine (TTA) via dual Fenton- and enzyme-mediated reactions. By varying the concentration of Fenton's reagent, the DN hydrogels were rapidly formed with controllable gelation rate. Importantly, the DN hydrogels showed a 13-fold increase in compressive strength and a 14-fold increase in tensile strength, compared to the single network hydrogels. The mechanical properties, elasticity, and plasticity of DN hydrogels could also be modulated by simply varying the preparation conditions, including the cross-linking density and reagent concentrations. At low cross-linker concentration (<0.05 wt %), the plastic DN hydrogel stretched to over 6,500%, whereas high cross-linker concentration (≥0.05 wt %) induced fully elastic hydrogels, without hysteresis. Besides, DN hydrogels were endowed with rapid self-recovery and highly enhanced adhesion, which can be further applied to wearable devices. Moreover, human dermal fibroblasts treated with DN hydrogels retained viability, demonstrating the biocompatibility of the cross-linking system. Therefore, we expect that the dual Fenton-/enzyme-mediated cross-linkable DN hydrogels offer great potential as advanced biomaterials applied for hard tissue regeneration and replacement.

Bridge-rich and loop-less hydrogel networks through suppressed micellization of multiblock polyelectrolytes

Most triblock copolymer-based physical hydrogels form three-dimensional networks through micellar packing, and formation of polymer loops represents a topological defect that diminishes hydrogel elasticity. This effect can be mitigated by maximizing the fraction of elastically effective bridges in the hydrogel network. Herein, we report hydrogels constructed by complexing oppositely charged multiblock copolymers designed with a sequence pattern that maximizes the entropic and enthalpic penalty of micellization. These copolymers self-assemble into branched and bridge-rich network units (netmers), instead of forming sparsely interlinked micelles. We find that the storage modulus of the netmer-based hydrogel is 11.5 times higher than that of the micelle-based hydrogel. Complementary coarse grained molecular dynamics simulations reveal that in the netmer-based hydrogels, the numbers of charge-complexed nodes and mechanically reinforcing bridges increase substantially relative to micelle-based hydrogels.

Tough and Elastic Cellulose Composite Hydrogels/Films for Flexible Wearable Sensors.

Cellulose and its composites, despite being abundant and sustainable, are typically brittle with very low flexibility/stretchability. This study reports a solution processing method to prepare porous, amorphous, and elastic cellulose hydrogels and films. Native cellulose dissolved in a water-ZnCl2 mixture can form ionic gels through in situ polymerization of acrylic acid (AA) to poly(acrylic acid) (PAA). The addition of up to 30 vol % AA does not change the solubility of cellulose in the water-ZnCl2 mixture. After polymerization, the formation of interpenetrated networks, resulting from the chemical cross-linking of PAA and the ionic/coordination binding among cellulose/PAA and ZnCl2, gives rise to strong, transparent, and ionically conductive hydrogels. These hydrogels can be used for wearable sensors to detect mechanical deformation under stretching, compression, and bending. Upon removal of ZnCl2 and drying the gels, semitransparent amorphous cellulose composite films can be obtained with a Young's modulus of up to 4 GPa. The rehydration of these films leads to the formation of tough, highly elastic composites. With a water content of 3-10.5%, cellulose-containing films as strong as paper also show typical characteristics of elastomers with an elongation of up to 1300%. Such composite films provide an alternative solution to resolving the material sustainability of natural polymers without compromising their mechanical properties.

Fabrication of highly stretchable composite organohydrogel for strain sensors with high sensitivity and broad temperature tolerance

Elastically stretchable conductive hydrogels have garnered significant scholarly interest for their potential applications in wearable sensing technologies. Yet, these highly elastic hydrogels often display diminished sensory capacities, particularly under conditions of severe thermal variation. This investigation unveils a highly stretchable composite organohydrogel distinguished by its superior sensory proficiency and resilience to harsh thermal environments. Encapsulating carbonized crepe paper (CCP) within a hydrophobic association-driven organohydrogel-crafted through the micellar copolymerization of hydrophobic stearyl methacrylate with hydrophilic acrylamide, and incorporation of polyvinyl alcohol (PVA) and Al3+ in a binary solvent of glycerol and water-we attained a high stretchability of 3865 %, in conjunction with augmented tensile strength and sensory acuity. Moreover, this composite demonstrates a gauge factor of 263.1 for strains ranging from 400 to 550 %, a detection threshold of 0.1 %, swift response/recovery times (161/152 ms), and sustained durability over 1000 cycles at a 100 % strain. Such attributes facilitate its deployment in the realms of health monitoring, activity sensing, gesture recognition, and wireless motion control, even under extreme thermal conditions, heralding a pioneering strategy for the creation of cost-efficient, high-efficacy electronic conductive hydrogels.

The characterization of cell traction force on nonflat surfaces with different curvature by elastic hydrogel microspheres.

It is of great importance to study the detachment/attachment behaviors of cells (cancer cell, immune cell, and epithelial cell), as they are closely related with tumor metastasis, immunoreaction, and tissue development at variety scales. To characterize the detachment/attachment during the interaction between cells and substrate, some researchers proposed using cell traction force (CTF) as the indicator. To date, various strategies have been developed to measure the CTF. However, these methods only realize the measurements of cell passive forces on flat cases. To quantify the active CTF on nonflat surfaces, which can better mimic the in vivo case, we employed elastic hydrogel microspheres as a force sensor. The microspheres were fabricated by microfluidic chips with controllable size and mechanical properties to mimic substrate. Cells were cultured on microsphere and the CTF led to the deformation of microsphere. By detecting the morphology information, the CTF exerted by attached cells can be calculated by the in-house numerical code. Using these microspheres, the CTF of various cells (including tumor cell, immunological cell, and epithelium cell) were successfully obtained on nonflat surfaces with different curvature radii. The proposed method provides a versatile platform to measure the CTF with high precision and to understand the detachment/attachment behaviors during physiology processes.

Scaled Elastic Hydrogel Interfaces for Brain Electrophysiology

AbstractThe advancement in brain–computer interface technology has facilitated real‐time communication between the brain and external devices, rapidly expanding invasive brain–computer interfaces. Nevertheless, little progress has been made in improving the one‐way, noninvasive brain–computer interface technology using conductive methods, necessitating enhancements to the current paste contact electrodes. In this paper, a captivating spherical electrode is fabricated that exhibits noncytotoxic properties, combining alginate hydrogel with indium tin oxide conductor components. The electrode's remarkable and consistent electrical conductivity enables it to generate stable adaptive deformations that conform to diverse scalp topographies. Most impedance values fall below 10 kΩ, indicating heightened hydrophilicity compared to traditional conductive pastes, as evidenced by contact angle measurements. An empirical electroencephalography data collection study confirms its conductivity and signal transmission reliability. The acquired electroencephalography signals are utilized for emotion recognition utilizing band energy ratio analysis and support vector machine (SVM) algorithms. The operation of this system is both straightforward and convenient, requiring minimal preparation before and after the collection of electroencephalography signals. Utilizing an extensive range of raw materials and straightforward preparatory procedures enhances the potential industrial application of hydrogel electrodes, thereby significantly contributing to advancing civilian electroencephalography equipment and investigating depression‐related pathologies.

Viscoelasticity, morphology, and molecular diffusion in structurally controlled ternary poly(acrylic acid) and nonionic surfactant-based hydrogels

Hydrogels are among the most promising materials for biological applications mainly because of their ability to absorb large volumes of water and carry as well as deliver biologically active substances. A challenge is to make them appropriately responsive to environmental triggering factors simply and reliably. In this work, we present a basic approach of modification of a commonly used, low-cost poly (acrylic acid) – PAA – hydrogel with biocompatible surfactants regarding their possible thermoresponsive activity.Viscoelasticity, hydration, and molecular diffusion processes, in relation to the morphology of the hydrogel and its mixture with nonionic surfactant Brij 58, are studied systematically using oscillatory rheometry, NMR diffusiometry and imaging, and cryoSEM. Our results contribute to the understanding of interactions between weak PAA and nonionic surfactants. The changes of the hydrogel microstructure caused by nonionic and bio-safe surfactant or thermal induction are clearly reflected in their mechanical response as well as the translational mobility of water molecules entrapped within the hydrogel's network. The structural modification induced by adding nonionic surfactant gives rise to a decrease in hydrogel elasticity.

Hydrogel morphogenesis induced by force-controlled growth

Morphogenesis is one of the most marvelous natural phenomena. The morphological characteristics of biological organs develop through growth, which is often triggered by mechanical force. In this study, we propose a bioinspired strategy for hydrogel morphogenesis through force-controlled chemical reaction and growth under isothermal conditions. We adopted a double network (DN) hydrogel with sacrificial bonds. Applying mechanical force to the gel caused deformation and sacrificial bond rupture. By supplying monomers to the gel, the radicals generated by the bond rupture triggered the formation of a new network inside the deformed gel. This new network conferred plasticity to the elastic gel, allowing it to maintain its deformed shape, along with increased volume and strength. We demonstrated that sheet-shaped DN hydrogels rapidly adopted various three-dimensional shapes at ambient temperature when subjected to forces such as drawing and blowing. This mechanism enables morphogenesis of elastic hydrogels and will promote the application of these materials in biomedical fields and soft machines.

Improvement of Alginate Extraction from Brown Seaweed (Laminaria digitata L.) and Valorization of Its Remaining Ethanolic Fraction.

This study aimed to improve the conventional procedure of alginate isolation from the brown seaweed (Laminaria digitata L.) biomass and investigate the possibility of further valorization of the ethanolic fraction representing the byproduct after the degreasing and depigmentation of biomass. The acid treatment of biomass supported by ultrasound was modeled and optimized regarding the alginate yield using a response surface methodology based on the Box-Behnken design. A treatment time of 30 min, a liquid-to-solid ratio of 30 mL/g, and a treatment temperature of 47 °C were proposed as optimal conditions under which the alginate yield related to the mass of dry biomass was 30.9%. The use of ultrasonic radiation significantly reduced the time required for the acid treatment of biomass by about 4 to 24 times compared to other available conventional procedures. The isolated alginate had an M/G ratio of 1.08, which indicates a greater presence of M-blocks in its structure and the possibility of forming a soft and elastic hydrogel with its use. The chemical composition of the ethanolic fraction including total antioxidant content (293 mg gallic acid equivalent/g dry weight), total flavonoid content (14.9 mg rutin equivalent/g dry weight), contents of macroelements (the highest content of sodium, 106.59 mg/g dry weight), and microelement content (the highest content of boron, 198.84 mg/g dry weight) was determined, and the identification of bioactive compounds was carried out. The results of ultra high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry analysis confirmed the presence of 48 compounds, of which 41 compounds were identified as sugar alcohol, phenolic compounds, and lipids. According to the 2,2-diphenyl-1-picrylhydrazyl assay, the radical scavenging activity of the ethanolic fraction (the half-maximal inhibitory concentration of 42.84 ± 0.81 μg/mL) indicated its strong activity, which was almost the same as in the case of the positive control, synthetic antioxidant butylhydroxytoluene (the half-maximal inhibitory concentration of 36.61 ± 0.79 μg/mL). Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis, and Bacillus cereus) were more sensitive to the ethanolic fraction compared to Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa, and Shigella sonnei). The obtained results indicated the possibility of the further use of the ethanolic fraction as a fertilizer for plant growth in different species and antifouling agents, applicable in aquaculture.