Natural Jellyfish Research Articles

Jellyfish Collagen Grafted with Hydroxybutyl Chitosan and Protocatechuic Acid Adhesive Sponge with Antibacterial Activity for Rapid Hemostasis.

Natural jellyfish collagen (JC) has garnered significant attention in the field of hemostasis due to its oceanic origin, nontoxicity, biodegradability, and absence of complications related to diseases and religious beliefs. However, the hemostatic performance of pure JC is limited by its poor stability, adhesion to wet tissue, and mechanical properties. We developed a novel (HJP) sponge comprising JC, protocatechuic acid (PA), and hydroxybutyl chitosan (HS) to enhance the application of JC in emergency hemostasis. This sponge exhibits antibacterial properties, good biocompatibility, wet tissue adhesion, and hemostatic capabilities. The HJP sponge demonstrates excellent thermal stability and mechanical strength (tensile strength: ∼106.6 kPa, compressive strength at 70% compressive strain: ∼1013.5 kPa) and strong wet tissue adhesion (∼117.1 kPa). Upon application to a wound, the HJP sponge rapidly forms a wound seal, achieving effective hemostasis through the synergistic action of PA and JC. The blood loss was also reduced to 0.105 g when compared to a commercial gelatin sponge. This JC-based sponge, with its multifaceted characteristics, holds significant promise for rapid hemostasis in clinical applications.

Performance evaluation of the static thrust and efficiency of an actuated biomimetic jellyfish model

Abstract This study offers an in-depth analysis of a jellyfish-inspired robotic model designed to simulate the expansion and contraction mechanisms found in natural jellyfish. By employing variable Duty Cycles to replicate the cyclic motions of the jellyfish, the thrust generation of the model is measured through static thrust assessments using a load cell, while its efficiency is evaluated using the Thrust-to-Power Ratio, TPR. The findings indicate that increasing the amplitude of the motion leads to more complex wave patterns, which in turn reduce the peak-to-peak force generated. Specifically, a 25% increase in the A/D ratio results in a significant 30% decrease in static thrust. It was observed that higher actuation frequencies do not notably influence thrust generation when the A/D ratio remains constant. Importantly, the TPR was found to be highest at an A/D ratio of 0.10, with an increase of up to 6% observed at higher Duty Cycles, suggesting that smaller actuation amplitudes are more efficient in enhancing thrust performance. These results highlight the critical role of amplitude in the efficiency of static thrust generation within a given Duty Cycle, emphasizing that lower amplitudes generally lead to higher efficiency. The study underscores the importance of optimizing both geometric and kinematic parameters for improved propulsion performance. It suggests that future research should focus on fine-tuning A/D ratios and Duty Cycles, as well as exploring alternative geometric configurations and materials to further enhance the hydrodynamic performance of jellyfish-inspired robots. The insights gained from this study provide a valuable foundation for developing more efficient and effective bio-inspired underwater vehicles.

Electromechanical enhancement of live jellyfish for ocean exploration.

The vast majority of the ocean's volume remains unexplored, in part because of limitations on the vertical range and measurement duration of existing robotic platforms. In light of the accelerating rate of climate change impacts on the physics and biogeochemistry of the ocean, the need for new tools that can measure more of the ocean on faster timescales is becoming pressing. Robotic platforms inspired or enabled by aquatic organisms have the potential to augment conventional technologies for ocean exploration. Recent work demonstrated the feasibility of directly stimulating the muscle tissue of live jellyfish via implanted microelectronics. We present a biohybrid robotic jellyfish that leverages this external electrical swimming control, while also using a 3D printed passive mechanical attachment to streamline the jellyfish shape, increase swimming performance, and significantly enhance payload capacity. A six-meter-tall, 13 600 l saltwater facility was constructed to enable testing of the vertical swimming capabilities of the biohybrid robotic jellyfish over distances exceeding 35 body diameters. We found that the combination of external swimming control and the addition of the mechanical forebody resulted in an increase in swimming speeds to 4.5 times natural jellyfish locomotion. Moreover, the biohybrid jellyfish were capable of carrying a payload volume up to 105% of the jellyfish body volume. The added payload decreased the intracycle acceleration of the biohybrid robots relative to natural jellyfish, which could also facilitate more precise measurements by onboard sensors that depend on consistent platform motion. While many robotic exploration tools are limited by cost, energy expenditure, and varying oceanic environmental conditions, this platform is inexpensive, highly efficient, and benefits from the widespread natural habitats of jellyfish. The demonstrated performance of these biohybrid robots suggests an opportunity to expand the set of robotic tools for comprehensive monitoring of the changing ocean.

SoJel –A 3D printed jellyfish-like robot using soft materials for underwater applications

Mass manufactured, biologically inspired soft robots are needed for safe robot-animal interactions. The key challenges are the design and manufacture of high-performance robots that meet stringent requirements in ocean environments. This work describes a 92% 3D-printed jellyfish-inspired soft robot, SoJel, which uses soft polymers for the bell and sensors. We show how slight variations in geometry affects the swimming performance of the robot, which demonstrates the need for advanced or custom-made 3D printers that avoid the difficulties in realizing controlled geometries by using traditional molding and casting techniques. The design reproduces important kinematic patterns of natural jellyfish, like the bell bending angle, actuation duty cycle, and bell kinematics. This work builds on previous generations of jellyfish-inspired robots that employed various types of actuators, but is largely polymer based, so it avoids metallic components that are susceptible to corrosion in the ocean. The realized cost of transport and vertical swimming height of robots powered by coiled nickel-titanium actuators are comparable to previous designs, however, the present robots have advantages in ease of design and manufacturing. A variety of soft robots and flexible structures can potentially be fabricated using this design principle. Flexible 3D-printed soft sensors enable us to determine the bending angles for motion estimation and control. Energy harvesting from water oscillation or free vibration is demonstrated using a twistron harvester and a piezoelectric composite integrated into the robot, which can be used for powering electronics, such as a LED for display and communication.

Mechanism of nanoplastics capture by jellyfish mucin and its potential as a sustainable water treatment technology

The accumulation of nanoplastics (NPs) in the environment has raised concerns about their impact on human health and the biosphere. The main aim of this study is to understand the mechanism that governs the capture of NPs by jellyfish mucus extracted from the jellyfish Aurelia sp. (A.a.) and compare the capture/removal efficiency to that of conventional coagulants and mucus from other organisms. The efficacy of A.a mucus to capture polystyrene and acrylic NPs (∼100 nm) from spiked wastewater treatment plant (WWTP) effluent was evaluated. The mucus effect on capture kinetics and destabilization of NPs of different polymer compositions, sizes and concentrations was quantified by means of fluorescent NPs, dynamic light scattering and zeta potential measurements and visualized by scanning electron microscopy. A dosing of A.a. mucus equivalent to protein concentrations of ∼2–4 mg L−1 led to a rapid change in zeta potential from a baseline of −30 mV to values close to 0 mV, indicating a marked change from a stable to a non-stable dispersion leading to a rapid (<10 min) and significant removal of NPs (60 %–90 %) from a stable suspension. The A.a. mucus outperformed all other mucus types (0–37 %) and coagulants (0 %–32 % for ferric chloride; 23–40 % for poly aluminum chlorohydrate), highlighting the potential for jellyfish mucus to be used as bio-flocculant. The results indicate a mucus-particle interaction consisting of adsorption-bridging and “mesh” filtration. Further insight is provided by carbohydrate composition and protein disruption analysis. Total protein disruption resulted in a complete loss of the A.a. mucus capacity to capture NPs, while the breaking of disulfide bonds and protein unfolding resulted in improved capture capacity. The study demonstrates that natural jellyfish mucin can capture and remove NPs in water and wastewater treatment systems more efficiently than conventional coagulants, highlighting the potential for development of a new type of bio-flocculant.

Discovery of a novel jellyfish venom metalloproteinase inhibitor from secondary metabolites isolated from jellyfish-derived fungus Aspergillus versicolor SmT07

The major jellyfish stings that occur in China are caused by scyphozoan Nemopilema nomurai, whose venom exhibits significant metalloproteinase activity that contributes to the toxic effects of jellyfish envenomation. Researching effective inhibitors suppressing the metalloproteinase activity of jellyfish venom represents a new attempt to cure jellyfish envenomations. In the present study, secondary metabolites produced by the jellyfish-associated fungus Aspergillus versicolor SmT07 were isolated and evaluated for their anti-proteolytic activities. Two xanthones, sterigmatocystin (JC-01) and oxisterigmatocystin C (JC-06), and four alkaloids, cottoquinazoline A (JC-02), phenazine-1-carboxylic acid (JC-03), viridicatin (JC-04) and viridicatol (JC-05), were isolated and identified. Only phenazine-1-carboxylic acid (PCA) showed significant anti-proteolytic activity of jellyfish venom assayed on azocasein, and the IC50 value was 2.16 mM. PCA also significantly inhibited fibrinogenolytic activity, protecting the Bβ chain of fibrinogen from degradation when preincubated with jellyfish venom at a ratio of >1:0.6 (PCA:venom, w/w). Molecular docking with several well-characterized snake venom metalloproteinases suggested the venom metalloproteinases inhibitory property of PCA by forming complex interactions with the active site via hydrogen bonds, π-π stacking and salt bridges, which was distinct from the binding mode of batimastat. The present study represents the first study identifying natural jellyfish venom metalloproteinase inhibitors from marine natural products, which may provide an alternative to develop therapeutic agents for treating jellyfish envenomations.

Generation of Chemobrionic Jellyfish‐Like Structures That Mechanically Divide and Exhibit Biomimetic “Symbiosis”

AbstractAddition of CaCl2into a highly alkaline phosphate buffer results in the generation of submerged transparent chemobrionic bubbles mimicking jellyfish that are stable and malleable. A compartmentalized O2‐generating reaction triggered the growth of regular vertical chemical gardens from the bubble through a gas micro‐rocket propelled mechanism. The bubbles can mechanically separate to yield two daughter bubbles in a process reminiscent of cytokinesis or natural jellyfish regeneration, and then re‐grow through new injection of CaCl2. Finally, loading ofE. colibacteria genetically engineered to exert green fluorescence inside the bubbles was demonstrated in a biomimetic analogue of “symbiosis”.

Developing Biohybrid Robotic Jellyfish (Aurelia aurita) for Free-swimming Tests in the Laboratory and in the Field.

Biohybrid robotics is a growing field that incorporates both live tissues and engineered materials to build robots that address current limitations in robots, including high power consumption and low damage tolerance. One approach is to use microelectronics to enhance whole organisms, which has previously been achieved to control the locomotion of insects. However, the robotic control of jellyfish swimming offers additional advantages, with the potential to become a new ocean monitoring tool in conjunction with existing technologies. Here, we delineate protocols to build a self-contained swim controller using commercially available microelectronics, embed the device into live jellyfish, and calculate vertical swimming speeds in both laboratory conditions and coastal waters. Using these methods, we previously demonstrated enhanced swimming speeds up to threefold, compared to natural jellyfish swimming, in laboratory and in situ experiments. These results offered insights into both designing low-power robots and probing the structure-function of basal organisms. Future iterations of these biohybrid robotic jellyfish could be used for practical applications in ocean monitoring.

Giant "Breathing" Proteinosomes with Jellyfish-like Property.

The design and construction of "breathing" self-assemblies has been a rather popular topic due to their potential in materials science and nanotechnology. Inspired by the "breathing" behavior of natural jellyfish, herein, we presented the construction of a giant "breathing" proteinosome through an interfacial self-assembly of proteins and surfactants at the oil/water interface of emulsions: The proteinosome displays "breathing" behavior and can swell and shrink for multiple cycles by protein folding and unfolding through the alternate addition and removal of denaturant; more importantly, when green fluorescent proteins were selected as alternative protein building blocks, the fluorescence of proteinosome can be reversibly switched on/off just like the behavior of jellyfish. Moreover, accompanied by reversible swelling and shrinking and on/off fluorescence, the expanded and shrunk membrane pore can be tuned for distinguishing quantum dots of different sizes. The folding-responsive breathing behavior of intelligent proteinosomes provides a platform for functional biomaterials.

Untethered soft robotic jellyfish

Inspired by natural creatures, soft robots possess the unique advantages of large actuation and excellent adaptability. Untethered designs of soft robots are drawing more attention to researchers, but current research is limited. Also, there is an increasing need to improve the performance of bio-mimetic robots. This work describes an untethered soft robotic jellyfish with high mobility that can mimic a natural jellyfish’s performance. The electrode of the robotic jellyfish is made by sandwiching carbon grease between two layers of dielectric elastomer film. The frame of the material, where six plastic paddles are attached, is made from a silicone elastomer. The robotic jellyfish has a maximum recorded swim speed of up to 1 cm s−1, with a peak thrust force of 0.000 12 N. A finite element simulation is developed to study the performance of the robotic jellyfish in a theoretical manner. By embedding a compact remote-controlled power source, the robotic jellyfish is made autonomous. In this case, the max peak speed is around 0.5 cm s−1. Ultimately, the working principles of the bio-mimetic robotic jellyfish can be useful in field studies and to guide the design of soft robots and flexible devices.

Aurelia aurita Inspired Artificial Mesoglea

In this preliminary study, we report the mechanical and dielectric properties of polyvinyl alcohol (PVA)-ferritin hydrogel. This material was found to exhibit close resemblance to Aurelia aurita (jellyfish) mesoglea in terms of stiffness modulus and water content. Systematic experiments were conducted on natural jellyfish to identify its compression modulus a function of deformation. In compressive testing Aurelia aurita mesoglea was found to exhibit nonlinear modulus in the range of −10 kPa to 70 kPa depending upon the compressive strain (0–50% strain). The negative stiffness is an artifact of tensile force experienced by the specimen at the beginning of the test due to surface tension. PVA hydrogels with 60% water to dimethyl sulfoxide (DMSO) ratio without ferritin particle (H60) and PVA hydrogels with 80% water to DMSO ratio with ferritin particle (F80) provided a good alternative to natural jellyfish mesoglea exhibiting shear modulus of 33.06 Pa and 39.99 Pa respectively as compared to 4.75 Pa for Aurelia aurita mesoglea. This is a significantly better match compared to the 1041.67 Pa shear modulus of Ecoflex, a soft polymer material commonly used in biomimetic robotics. A Mooney Rivlin model suggests that H60 and F80 compositions are about 6.9 times and 8.4 times stiffer than natural Aurelia aurtia mesoglea whereas Ecoflex is 219 times as stiff. Nanocomposite hydrogel consisting of PVA matrix and ferritin nanoparticles were found to exhibit higher durability over regular PVA hydrogels and had more consistent properties due to increased cross-linking at ferritin nanoparticle sites. The ferritin nanoparticles were found to act as springs, increasing the modulus by increasing the surface area of the cross-linked polymer chains and disrupting long linear chain patterns of the polymer. Natural Aurelia aurita was found to have water content of 96.3% with a standard deviation of 0.57% as compared to 85% water content of PVA-ferritin hydrogels. Use of this material in the design of biomimetic unmanned underwater vehicles is expected to reduce the power consumption, increase swimming efficiency, and better replicate the rowing kinematics of naturally occurring Aurelia aurita.

Hydrogen-fuel-powered bell segments of biomimetic jellyfish

Artificial muscles powered by a renewable energy source are desired for joint articulation in bio-inspired autonomous systems. In this study, a robotic underwater vehicle, inspired by jellyfish, was designed to be actuated by a chemical fuel source. The fuel-powered muscles presented in this work comprise nano-platinum catalyst-coated multi-wall carbon nanotube (MWCNT) sheets, wrapped on the surface of nickel–titanium (NiTi) shape memory alloy (SMA). As a mixture of oxygen and hydrogen gases makes contact with the platinum, the resulting exothermic reaction activates the nickel–titanium (NiTi)-based SMA. The MWCNT sheets serve as a support for the platinum particles and enhance the heat transfer due to the high thermal conductivity between the composite and the SMA. A hydrogen and oxygen fuel source could potentially provide higher power density than electrical sources. Several vehicle designs were considered and a peripheral SMA configuration under the robotic bell was chosen as the best arrangement. Constitutive equations combined with thermodynamic modeling were developed to understand the influence of system parameters that affect the overall actuation behavior of the fuel-powered SMA. The model is based on the changes in entropy of the hydrogen and oxygen fuel on the composite actuator within a channel. The specific heat capacity is the dominant factor controlling the width of the strain for various pulse widths of fuel delivery. Both theoretical and experimental strains for different diameter (100 and 150 µm) SMA/MWCNT/Pt fuel-powered muscles with dead weight attached at the end exhibited the highest magnitude under 450 ms of fuel delivery within 1.6 mm diameter conduit size. Fuel-powered bell deformation of 13.5% was found to be comparable to that of electrically powered (29%) and natural jellyfish (42%).

A biomimetic robotic jellyfish (Robojelly) actuated by shape memory alloy composite actuators

An analysis is conducted on the design, fabrication and performance of an underwater vehicle mimicking the propulsion mechanism and physical appearance of a medusa (jellyfish). The robotic jellyfish called Robojelly mimics the morphology and kinematics of the Aurelia aurita species. Robojelly actuates using bio-inspired shape memory alloy composite actuators. A systematic fabrication technique was developed to replicate the essential structural features of A. aurita. Robojelly's body was fabricated from RTV silicone having a total mass of 242 g and bell diameter of 164 mm. Robojelly was able to generate enough thrust in static water conditions to propel itself and achieve a proficiency of 0.19 s−1 while the A. aurita achieves a proficiency of around 0.25 s−1. A thrust analysis based on empirical measurements for a natural jellyfish was used to compare the performance of the different robotic configurations. The configuration with best performance was a Robojelly with segmented bell and a passive flap structure. Robojelly was found to consume an average power on the order of 17 W with the actuators not having fully reached a thermal steady state.

Gene Expression of GFP from jellyfish into fish.

he green-fluorescent protein (GFP) of the jellyfish Aequorea victoria has recently been used as a universal reporter in a broad range of heterologous living cells and organisms. Fertilized eggs of the Carp (Cyprinus carpio) in the period of blastodisc formation and up to the fourth division of the cleavage were injected with two plasmids expressing the natural jellyfish GFP and synthetic engineered jellyfish (sGFP) using Microinjection method. Reverse transcription PCR products, cloning, sequencing, were analysed. Using universal transcription and translation enhancers with strong promoters, has been showed that GFP signals are detectable in transient expression systems of fish. The engineered GFP gene sequence gave higher GFP expression in fish than the natural jellyfish GFP sequence. This new tool can be used for studies of gene regulation, signal transduction, development and cell biology in animals and plants.