Mixture Of Gelatin Research Articles

Reduced graphene oxide–reinforced tricalcium phosphate/gelatin/chitosan light-responsive scaffolds for application in bone regeneration

Bone is a mineralized tissue with the intrinsic capacity for constant remodeling. Rapid prototyping techniques, using biomaterials that mimic the bone native matrix, have been used to develop osteoinductive and osteogenic personalized 3D structures, which can be further combined with drug delivery and phototherapy. Herein, a Fab@Home 3D Plotter printer was used to promote the layer-by-layer deposition of a composite mixture of gelatin, chitosan, tricalcium phosphate, and reduced graphene oxide (rGO). The phototherapeutic potential of the new NIR-responsive 3D_rGO scaffolds was assessed by comparing scaffolds with different rGO concentrations (1, 2, and 4 mg/mL). The data obtained show that the rGO incorporation confers to the scaffolds the capacity to interact with NIR light and induce a hyperthermy effect, with a maximum temperature increase of 16.7 °C after under NIR irradiation (10 min). Also, the increase in the rGO content improved the hydrophilicity and mechanical resistance of the scaffolds, particularly in the 3D_rGO4. Furthermore, the rGO could confer an NIR-triggered antibacterial effect to the 3D scaffolds, without compromising the osteoblasts' proliferation and viability. In general, the obtained data support the development of 3D_rGO for being applied as temporary scaffolds supporting the new bone tissue formation and avoiding the establishment of bacterial infections.

Encapsulation of grape seed oil in oil-in-water emulsion using multilayer technology: Investigation of physical stability, physicochemical and oxidative properties of emulsions under the influence of the number of layers

Many studies have shown that grape seed oil (GSO) is one of the vegetable fats that are plentiful in essential fatty acids and can be used as a fat substitute or to modify fat in food products to reduce saturated fatty acids. However, due to its low solubility and high sensitivity to oxidation, it is necessary to develop delivery systems that can distribute GSO in food more effectively. Recently, the preparation of emulsions using the layer-by-layer (LBL) method has many advantages in delivering lipid-soluble functional compounds. This research was used to check the formation of GSO oil-loaded primary, secondary and tertiary multilayer emulsions stabilized by mixture of anionic gelatin, cationic chitosan, and anionic basil seed gum (BSG) as the aqueous phase at pH 5, prepared using a layer-by-layer electrostatic deposition technique. Multilayer emulsions prepared by GSO and a mixture of gelatin, chitosan, and BSG as the aqueous phase at pH 5. Finally, the effect of the number of layers on the physicochemical properties (particle size, viscosity, turbidity, refractive index, and physical stability) and oxidative stability (peroxide value, thiobarbituric acid value, and fatty acid profile) during the storage time (30 days) at two temperatures 25 °C & 4 °C was investigated. Also, the zeta potential and Fourier transform infrared spectroscopy (FTIR) of mono-layer and multi-layer emulsions were investigated. The results revealed that by increasing the number of layers of multi-layer emulsion of GSO, the stability has improved. Thus, the tertiary emulsion has been more effective than the other two emulsions in maintaining the physicochemical characteristics and stability over time (P < 0.001). Morphological characterization and FTIR spectroscopy results confirmed that gelatin, chitosan, and BSG were successfully loaded into the LBL emulsions. This study can improve the original percept of multilayer emulsions and promulgate their potential applications for the entire encapsulation of essential fatty acids to enrich and prevent peroxide attack.

A tilapia skin-derived gelatin hydrogel combined with the adipose-derived stromal vascular fraction for full-thickness wound healing.

Biomaterials are widely used in regenerative medicine to repair full-thickness skin defect wounds. The adipose-derived stromal vascular fraction (SVF) shows pro-regenerative properties, however, the ex vivo biological activity of SVF is suppressed due to the lack of an external scaffold. Tilapia skin, as a sustained and recyclable biomaterial with low immunogenicity, was applied in the preparation of a hydrogel. The mixture of tilapia skin-derived gelatin and methacrylic anhydride as a scaffold facilitated the paracrine function of SVF and exerted a synergistic effect with SVF to promote wound healing. In this study, 30% (w/v) SVF was added to methacrylate-functionalized tilapia skin gelatin and subsequently exposed to UV irradiation to form a three-dimensional nano-scaffolding composite hydrogel (FG-SVF-3). The effects of paracrine growth factors, neovascularization, and collagen production on wound healing were extensively discussed. FG-SVF-3 displayed a pronounced wound healing ability via in vivo wound models. The FG-SVF-3 hydrogel enhanced the biocompatibility and the expression of EGF, bFGF, and VEGF. FG-SVF-3, as a promising wound dressing, exhibited superior ability to accelerate wound healing, skin regeneration, and wound closure.

Formulation and Characterization of Blend Microspheres of Anti Diabetic Drug Glimepiride

The objective of the present investigation was to prepare polymeric blend microspheres of glimepiride for improving its half-life using chitosan and gelatin as the two polymers for preparing the blend. The blend microspheres of chitosan and gelatin were prepared by using different ratios of both the polymers as well as cross-linking agent, glutaraldehyde (GA), by emulsion cross-linking method. The optimum formulation was one which exhibited the lowest particles size and it was used to load glimepiride (20% by weight) of the polymers. The glimepiride loaded blend microspheres were evaluated for yield, drug polymer interaction, entrapment efficiency, surface study and in vitro release. The particle size of the blend microspheres was found to be in the range of 126.8 µm to 371.3 µm. The lowest particle size (126.8 ± 6.11 µm) was obtained in AF5 containing 50% of gelatin and 50% of chitosan. The FTIR spectra of the physical mixture of glimepiride, gelatin and chitosan displayed all the characteristic peaks of glimepiride, thus indicating that no incompatibility was present between the drug and the polymer. The SEM image of the drug loaded blend microsphere revealed spherical particles of irregular size with smooth surface. The average particles size of the glimepiride loaded blend microspheres was obtained to be 131.4 ± 9.7 µm with a yield of 91.6% by weight of the drug and polymers used for formulation of the microspheres. It was found that 82.4 ± 6.8% of glimepiride was found to be entrapped in the particles. The results of the in vitro release studies of the glimepiride loaded blend microsphere revealed that 71.49 ± 0.74 % glimepiride was released from the particles at the end of 12th hour of study.

Multifunctional Biodegradable Conductive Hydrogel Regulating Microenvironment for Stem Cell Therapy Enhances the Nerve Tissue Repair.

The nerve guidance conduits incorporated with stem cells, which can differentiate into the Schwann cells (SCs) to facilitate myelination, shows great promise for repairing the severe peripheral nerve injury. The innovation of advanced hydrogel materials encapsulating stem cells, is highly demanded for generating supportive scaffolds and adaptive microenvironment for nerve regeneration. Herein, this work demonstrates a novel strategy in regulating regenerative microenvironment for peripheral nerve repair with a biodegradable conductive hydrogel scaffold, which can offer multifunctional capabilities in immune regulation, enhancing angiogenesis, driving SCs differentiation, and promoting axon regrowth. The biodegradable conductive hydrogel is constructed by incorporation of polydopamine-modified silicon phosphorus (SiP@PDA) nanosheets into a mixture of methacryloyl gelatin and decellularized extracellular matrix (GelMA/ECM). The biomimetic electrical microenvironment performs an efficacious strategy to facilitate macrophage polarization toward a pro-healing phenotype (M2), meanwhile the conductive hydrogel supports vascularization in regenerated tissue through sustained Si element release. Furthermore, the MSCs 3D-cultured in GelMA/ECM-SiP@PDA conductive hydrogel exhibits significantly increased expression of genes associated with SC-like cell differentiation, thus facilitating the myelination and axonal regeneration. Collectively, both the in vitro and in vivo studies demonstrates that the rationally designed biodegradable multifunctional hydrogel significantly enhances nerve tissues repair.

Rheological and thermal properties of an enteral nutrition formula for nutritional support patients using a combined mixture of gelatin and maltodextrin.

Enteral nutrition is a type of nutritional support that provides the necessary sources of energy and protein for patients who suffer from dysphagia, chronic disease, and loss of appetite. In this study, a gelatin-maltodextrin binary biopolymer system has been incorporated into a semi-solid formula. The I-optimal combination design approach was used to create 19 formulations, and the dynamic rheological properties, dynamic laser scattering, and zeta potential responses were evaluated over 30 days of storage at 5°C. Solid viscoelastic behavior has been approved since G' > G″ in the frequency sweep test with no cross-over point. Maltodextrin may interfere within the gelatin network, and increasing the maltodextrin to gelatin (from 0.14 to 1) may lead to a wider linear viscoelastic (LVE) strain range (2.16%), a lower storage modulus at LVE (52%), a lower yield stress (46%), and a lower glass transition temperature (34%). The presence of maltodextrin may reduce the temperature of the sol-to-solid transformation by 48% and enhance its flexibility. In contrast, increasing the gelatin-to-maltodextrin ratio following melting at 37°C led to an increase in the cumulant mean and polydispersity index, indicating a relatively unstable system. The range of zeta potential values between -4.4 and 1.7 mV confirmed a tendency toward coagulation. Microscopic images revealed instability because of irregular or compact chains formed in the gelatin matrix by using higher amounts of maltodextrin. Finally, the best formula had the best rheological stability and was suitable for tube-feeding patients, with a gelatin-to-maltodextrin ratio of 4.35:3.64% w/w on day 17.4.

Ionizing Radiation Synthesis of Hydrogel Nanoparticles of Gelatin and Polyethylene Glycol at High Temperature.

Nanohydrogel particles of polyethylene glycol (PEG), gelatin (GEL), and PEG-GEL mixtures (MIXs) were synthesized with a high electron beam and 60Co gamma-ray radiation. The relatively novel technique of Asymmetrical Flow Field Flow Fractionation (AF4 or AFFFF) coupled to a Multi-Angle Laser Light Scattering (MALLS) detector was mainly used to determine the hydrodynamic diameter (Dh) of the radiation-synthesized PEG, GEL, and PEG-GEL nanohydrogel particles. Our approach to achieving nanohydrogel particles is to enhance the intracrosslinking reactions and decrease the intercrosslinking reactions of the C-centered radicals of the PEG and GEL. The intracrosslinking reactions of these free radicals were enhanced via irradiation at temperatures of 77-80 °C and using a high dose rate and pulsed irradiation. The shorter average distance between the C-centered free radicals on the backbone of the thermally collapsed PEG and GEL chain, due to the destruction of hydrogen bonds, enhances the intracrosslinking reactions. It was observed that increasing the dose and dose rate decreased the Dh. DLS results lined up with AF4 measurements. This study provides researchers with a clean method to produce GEL-PEG hydrogels without the use of toxic reagents. Particle size can be tuned with dose, dose rate, and temperature as demonstrated in this work. This is ideal for medical applications as the use of ionizing radiation eliminates toxicity concerns and provides simultaneous sterilization of the material.

Development of a membrane and a bilayer of chitosan, gelatin, and polyhydroxybutyrate to be used as wound dressing for the regeneration of rat excisional wounds.

The skin is the largest organ in the human body that acts as a protective barrier from the outside environment. Certain dermatological pathologies or significant skin lesions can result in serious complications. Several studies have focused on the development of tissue-engineered skin substitutes. In this study, a new bilayer scaffold composed of a chitosan-gelatin membrane and a chitosan-polyhydroxybutyrate (PHB) porous matrix was synthesized and populated with human adipose-derived mesenchymal stem cells (hASCs) to be potentially used for wound dressing applications. By combining this membrane and porous matrix with the stem cells, we aimed to provide immunomodulation and differentiation capabilities for the wound environment, as well as mechanical strength and biocompatibility for the underlying tissue. The membrane was prepared from the mixture of chitosan and gelatin in a 2:1 ratio and the porous matrix was prepared from the mixture of chitosan and PHB, in equal proportions to form a final solution at 2.5% (m/v). Fourier transform infrared spectroscopy analysis showed the formation of blends, and micro-computed tomography, scanning electron microscopy and atomic force microscopy images demonstrated membrane roughness and matrix porosity. The MTT assay showed that the scaffolds were biocompatible with hASC. The membrane and the bilayer were used as dressing and support for cell migration in the dorsal excisional wound model in Wistar rats. Histological and gene transcriptional analyses showed that the animals that received the scaffolds regenerated the hair follicles in the deep dermis in the central region of the wound. Our results demonstrate the potential of these new biomaterials as dressings in wound healing studies, favoring tissue regeneration.

Enhancing Rheological and Textural Properties of Gelatin-Based Composite Gels through Incorporation of Sesame Seed Oleosome-Protein Fillers.

In this study, the protein and oleosomes of sesame seeds were extracted individually and used to prepare a gel composed of gelatin, protein, and oleosomes. Mixtures of gelatin and sesame seeds protein were prepared, and oleosomes with different percentages (0, 10, 20 and 30% of their weight) were used. Different amounts of oleosomes in the composite gel samples were examined for their morphological, rheological, and textural properties. The results of the viscoelastic properties of different composite gel samples indicated that a higher percentage of oleosomes would increase the storage modulus (G'), loss modulus (G″), and complex viscosity (η*). The storage modulus of all gel samples was greater than the loss modulus, suggesting a solid behavior. So, in the sample with 30% oleosome, the storage modulus and the loss modulus reached 143,440 Pascals and 44,530 Pascals. The hardness and breaking force in samples containing 30% oleosome reached 1.29 ± 0.02 and 0.17 ± 0.02, respectively. In general, it can be said that composite gels based on gelatin-sesame seed protein modified with oleosome can be used as a part of food components in various dairy products, gelatin desserts, lean meat products and the production of useful products.

Strongly Metal-Adhesive and Self-Healing Gelatin@Polydopamine-Based Hydrogels with Long-Term Antioxidant Activity.

Bioinspired adhesives have been increasingly developed, especially towards a biomedical application. Therefore, in this study, dopamine (DA) was oxidized into polydopamine (PDA) in a gelatin mixture via titration with NaIO4 as a strong oxidant to easily obtain an adhesive antioxidant and self-healing PDA-gelatin hydrogel. Rheology experiments show a stiffness in the order of kPa and a thermal resistance above 50 °C, much above the gel-sol transition temperature of pristine gelatin. After heating at 55 °C, the gel is self-healing. In addition, just after formulation, it shows strong peeling-rate-dependent adhesion to steel with a tensile work per unit area (W) of up to 100 ± 39 J/m2, which is 2.5 times higher than that of the same gel without PDA at a peeling rate of 1000 µm/s. The increase in W between peeling rates of 10 and 1000 µm/s was studied and interpreted in terms of the gels' viscoelasticity. Moreover, this hydrogel offers significant antioxidant activity (measured by DPPH scavenging) that lasts with storage for at least over 15 days, this being then prolonged for 2 additional days, which seems particularly relevant considering the importance of reactive oxygen species (ROS) in wound healing. To summarize, PDA-gelatin gel is a promising strong and antioxidant adhesive.

LDH-doped gelatin-chitosan scaffold with aligned microchannels improves anti-inflammation and neuronal regeneration with guided axonal growth for effectively recovering spinal cord injury

Spinal cord injury (SCI) causes immune cell infiltration, neuronal death and permanent motor dysfunction. Effective treatment for SCI requires simultaneous suppression of the inhibitory and inflammatory microenvironment and enhancement of the pro-regenerative potential at SCI sites. However, realizing neuronal regeneration with guided axon growth and anti-inflammation simultaneously is currently challenging. In this study, a layered double hydroxides (LDH)-doped gelatin-chitosan scaffold with aligned microchannels (GC-LDH/A scaffold) combined with chemical and structural repair effects was developed to regulate immune microenvironment and promote directional neurogenesis. The GC-LDH/A scaffold was prepared by anisotropic freezing of a mixture of Mg-Fe layered double hydroxides (Mg-Fe LDH), gelatin and chitosan. The LDH, gelatin and aligned microchannel structure work together to promote neuronal regeneration. Chitosan and the aligned microchannel structure have a function of anti-inflammation while the latter also guides axonal growth. The repair effect of this scaffold was assessed by restoring a completely transected spinal cord injury, and the results showed that the GC-LDH/A scaffold effectively activated the anti-inflammatory polarization of macrophages and microglia, promoted neurogenesis and guided axonal growth from the rostral to caudal of the lesion site. The key mediator of functional recovery in SCI is Myosin II, which negatively regulates axonal growth; however, the aligned microchannel structure inhibits its activity and reverses the repair effect. This study provides a promising strategy for addressing the repair challenges for effective SCI treatment.

Liver dECM-Gelatin Composite Bioink for Precise 3D Printing of Highly Functional Liver Tissues.

In recent studies, liver decellularized extracellular matrix (dECM)-based bioinks have gained significant attention for their excellent compatibility with hepatocytes. However, their low printability limits the fabrication of highly functional liver tissue. In this study, a new liver dECM-gelatin composite bioink (dECM gBioink) was developed to overcome this limitation. The dECM gBioink was prepared by incorporating a viscous gelatin mixture into the liver dECM material. The novel dECM gBioink showed 2.44 and 10.71 times higher bioprinting resolution and compressive modulus, respectively, than a traditional dECM bioink. In addition, the new bioink enabled stable stacking with 20 or more layers, whereas a structure printed with the traditional dECM bioink collapsed. Moreover, the proposed dECM gBioink exhibited excellent hepatocyte and endothelial cell compatibility. At last, the liver lobule mimetic structure was successfully fabricated with a precisely patterned endothelial cell cord-like pattern and primary hepatocytes using the dECM gBioink. The fabricated lobule structure exhibited excellent hepatic functionalities and dose-dependent responses to hepatotoxic drugs. These results demonstrated that the gelatin mixture can significantly improve the printability and mechanical properties of the liver dECM materials while maintaining good cytocompatibility. This novel liver dECM gBioink with enhanced 3D printability and resolution can be used as an advanced tool for engineering highly functional liver tissues.

Two Affordable, High-Fidelity Central Venous Models for Ultrasound-Guided Interventional Training.

Ultrasound-guided vascular access is an increasingly popular technique due to its reduced complication and higher success rates. Commercially bought training phantoms allow providers to develop tactile skills in a low-risk setting, but are also expensive and poorly accessible. This study analyzes the efficacy of homemade, low-cost, gelatin-based central line vascular models to teach vascular anatomy and intravascular access techniques in training physicians. A gelatin mold was created using a mixture of unflavored gelatin, hot water, psyllium husk powder, and rubbing alcohol. Latex tubing, balloons, precooked hot dog, and tofu were inserted to simulate arteries, veins, nerves, and the sternocleidomastoid muscle, respectively. Medical students from a single institution participated in a 90-minute workshop led by interventional radiology residents. Participants completed presurveys and postsurveys that assessed knowledge acquisition and confidence levels related to acquiring central access. All images were obtained using a USB-C Butterfly iQ probe. Twenty medical students were analyzed after the workshop. There was a statistically significant increase in self-reported confidence in basic ultrasound use (adjusting gain, depth, probe manipulation), localizing major anatomical structures, using ultrasound for vessel access, and reported ease in identifying muscle, nerves, and major blood vessels under ultrasound. There was also a significant increase in correctly identified anatomical landmarks after the workshop, including the sternocleidomastoid muscle, internal jugular vein, carotid artery, femoral nerve, femoral artery, and femoral vein. Our findings suggest that our homemade, low-cost, gelatin-based models were effective in teaching vascular anatomy and ultrasound-guided vascular access techniques to training physicians.

In-situ elemental quantitative imaging in plant leaves by LA-ICP-MS with matrix-matching external calibration

Due to the enormous interest in plants related to bioscience, environmental and toxicological research, analytical methods are expected with the ability of getting information on elemental transfer, distribution and contents in plants. In this work, a mixture of gelatin (GA) and hydroxypropyl methyl cellulose (HPMC) was prepared to simulate plant matrix, a method based on laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) with matrix-matching external calibration was proposed for direct quantification of multiple elements in plants. The composition of GA&HPMC substrate was optimized, such as the concentration of spiked nitric acid, the mass fraction of both GA and HPMC in the substrate and the mass ratio of GA: HPMC. After spiking elemental solution, coating the mixture onto a glass slide and drying overnight at room temperature, GA&HPMC substrate was obtained. The substrate obtained with GA: HPMC of 8: 2 was used to fabricate the standard series, which exhibited good elemental homogeneity and similar elemental signal intensities in LA-ICP-MS detection to that obtained for plant Certified Reference Material (CRM). CRMs of different plants including Citrus leaf (GBW10019), Tea (GBW07605), Beans (GBW10021) and Scallions (GBW10049) were further pressed into pellets and subjected to the proposed method, and the quantification accuracy was demonstrated. The limits of detections of this method were found to be 0.003 (Ce)-104 (Ca) μg g−1, with a wide linear range (0.01–10000 μg g−1) for 17 target elements. The application potential of the method was further demonstrated by performing elemental imaging in Trigonotis peduncularis leaves. Rapid in-situ quantitative imaging of Zn, Cu, Sr and Mn was achieved, and the elemental quantitative distributions were discussed. The constructed substrate helped direct elemental quantification in plants. It provided a powerful and efficient tool for the investigation of the distribution and transfer of elements in plants, favoring further exploration of elemental bioavailability, transport and toxicity mechanisms.

Evaluation of long- and short-term storage conditions and efficiency of a novel microencapsulated Salmonella phage cocktail for controlling Salmonella in chicken meat.

This study aims to assess the stability and activity of using a lyophilization, formulation design and to evaluate their efficiency for controlling Salmonella in chicken meat. The phage-loaded 0.3M sucrose gelatin mixture at 4 and 25°C displayed significantly less phage titer loss (p < 0.05) than the other excipients and liquid phage cocktail in 12months. The results showed that there were significant reductions of Salmonella at the end of the storage in chicken meat for newly prepared phage powder (1.86 log CFU/cm2 and 2.18 log CFU/cm2), lyophilized phage powders stored at 4°C (1.08 log CFU/cm2 and 1.26 log CFU/cm2) and stored at 25°C (0.66 log CFU/cm2 and 1.00 log CFU/cm2) for 10months at MOI 100 and 1000, respectively. The results demonstrated that lyophilized phages in a simple food grade formulation can be successfully stored and might be used in biocontrol of Salmonella in meat.

3D bioprinting of a gelatin-alginate hydrogel for tissue-engineered hair follicle regeneration.

Hair follicle (HF) regeneration remains challenging, principally due to the absence of a platform that can successfully generate the microenvironmental cues of hair neogenesis. Here, we demonstrate a 3D bioprinting technique based on a gelatin/alginate hydrogel (GAH) to construct a multilayer composite scaffold simulating the HF microenvironment in vivo. Fibroblasts (FBs), human umbilical vein endothelial cells (HUVECs), dermal papilla cells (DPCs), and epidermal cells (EPCs) were encapsulated in GAH (prepared from a mixture of gelatin and alginate) and respectively 3D-bioprinted into the different layers of a composite scaffold. The bioprinted scaffold with epidermis- and dermis-like structure was subsequently transplanted into full-thickness wounds in nude mice. The multilayer scaffold demonstrated suitable cytocompatibility and increased the proliferation ability of DPCs (1.2-fold; P<0.05). It also facilitated the formation of self-aggregating DPC spheroids and restored DPC genes associated with hair induction (ALP, β-catenin, and α-SMA). The dermal and epidermal cells self-assembled successfully into immature HFs in vitro. HFs were regenerated in the appropriate orientation in vivo, which can mainly be attributed to the hierarchical grid structure of the scaffold and the dot bioprinting of DPCs. Our 3D printed scaffolds provide a suitable microenvironment for DPCs to regenerate entire HFs and could make a significant contribution in the medical management of hair loss. This method may also have broader applications in skin tissue (and appendage) engineering. STATEMENT OF SIGNIFICANCE: Hair loss remains a challenging clinical problem that influences quality of life. Three-dimensional (3D) bioprinting has become a useful tool for the fabrication of tissue constructs for transplantation and other biomedical applications. In this study, we used a 3D bioprinting technique based on a gelatin/alginate hydrogel to construct a multi-layer composite scaffold with cuticular and corium layers to simulate the microenvironment of dermal papilla cells (DPCs) in the human body. This new approach permits the controllable formation of self-aggregating spheroids of DPCs in a physiologically relevant extracellular matrix and the initiation of epidermal-mesenchymal interactions, which results in HF formation in vivo. The ability to regenerate entire HFs should have a significant impact on the medical management of hair loss.

Biodegradable Electrohydraulic Soft Actuators

Biodegradable materials decompose and return to nature. This functionality can be applied to derive robotic systems that are environmentally friendly. This study presents a fully biodegradable soft actuator, which is one of the key elements in “green” soft robotics. The working of the actuator is based on an electrohydraulic principle, which is similar to that of hydraulically amplified self‐healing electrostatic actuators. The actuator developed in this study consists of a dielectric film made of polylactic acid (PLA) and polybutylene adipate‐co‐terephthalate (PBAT), with soybean oil as the dielectric liquid and electrodes made from a mixture of gelatin, glycerol, and sodium chloride (NaCl). The synthesized biodegradable electrode material exhibits a Young's modulus of 0.06 MPa and resistivity of 258 Ω·m when the mass fraction of NaCl relative to the amount of gelatin and glycerol is 10 wt%. The softness and resistivity of the electrode material results in actuation strain values of 3.2% (at 1 kV, corresponding to 1.2 kV mm−1) and 18.6% (at 10 kV, corresponding to 9.6 kV mm−1) for the linear‐type and circular‐type actuators, respectively. These values obtained for the biodegradable electrohydraulic soft actuators are comparable to those of nonbiodegradable actuators of the same type, representing the successful implementation of the concept.

Hybrid polymeric Hydrogel-based biomaterials with potential applications in regenerative medicine

In the field of regenerative medicine, the use of biomaterials as scaffolds that provide structural integrity is key for tissue regeneration. In this context, hydrogels are considered a great option, due to their elastic properties and capacity to absorb large amounts of water while preserving their structure. Notably, both collagen and gelatin are considered good candidates for use due to their high biocompatibility. In particular, gelatin is a collagen derivative that has better biological properties at the expense of poorer mechanical properties. Therefore, the main objective of this work was the development and characterization of polymeric hydrogels based on collagen and gelatin. In this sense, hydrogels with different collagen/gelatin ratios were elaborated using cooling as the gelation method. Subsequently, different studies were carried out in order to evaluate their mechanical, thermal and microstructural properties, as well as their biocompatibility. The results showed that hydrogels formed from the mixture of collagen and gelatin retain, to a large extent, the good viscoelastic properties of collagen, while showing low levels of cytotoxicity and hemocompatibility similar to those obtained for gelatin. However, owing to the nature of the materials used, the thermal characteristics are not ideal for use in biomedicine, thus further studies are required to overcome these drawbacks.

Effect of clarification on some characteristics of pomegranate juice processed by two different methods during storage

This study aimed to assess the effectiveness of two clarifying procedures and their effects on some properties in thermally or microwave-pasteurized pomegranate juices. The experiment consisted in combining pectinase and protease as well as chitosan and gelatin once they were being stored in the refrigerator. The experiment consisted in three parts, being the first one a fresh juice without any clarification treatment, whereas, the second one was the fresh juice treated with clarifying agent consisted of pectinase and protease mixture ratio (2:1) at 0.75 v/v,and 50 °C for 20 min. Finally, the third one was fresh juice treated with chitosan and gelatin mixture at 0.4 and 0.8) g/L, respectively, at 50 °C for (20) min. The pasteurization of all three experiments was done by using two techniques, i.e., one with thermal water bath at 85 °C for two min and the microwave at 400 Watts for two min. All pomegranate juice bottles were stored at 4 °C for three months. The results showed a significant effect of the clarification method variable on the properties studied, especially turbidity, polyphenol and anthocyanin values. Moreover, the juice clarified with the enzymatic clarification method had better characteristics than the traditional ones during storage, what has therefore a better commercial appeal. The area of significance was founded with the use of traditional clarification with concentration at (0.4 and 0.8) g/l, and microwave pasteurization with 400 watts and zero month of storage at 4 °C, respectively, which is provided a minimum turbidity value.

Multifunctional Double-Layer and Dual Drug-Loaded Microneedle Patch Promotes Diabetic Wound Healing.

Chronic nonhealing diabetic wounds are a serious complication of diabetes, with a high morbidity rate that can cause disability or death. The long period of inflammation and dysfunctional angiogenesis are the main reasons for wound-healing difficulty in diabetes. In this study, a multifunctional double-layer microneedle (DMN) is constructed to control infection and promote angiogenesis, meeting the multiple demands of the healing process of a diabetic wound. The double-layer microneedle is consisted in a hyaluronic acid substrate and a mixture of carboxymethyl chitosan and gelatin as the tip. The antibacterial drug tetracycline hydrochloride (TH) is loaded into the substrate of the microneedle to achieve rapid sterilization and promote resistance to external bacterial infections. The microneedle tip loaded with recombinant human epidermal growth factor (rh-EGF) is inserted into the skin, in response to gelatinase produced by resident microbe and disassociate to achieve the enzymatic response release. The double-layer drug-loaded microneedles (DMN@TH/rh-EGF) have antibacterial and antioxidant effects, and promote cell migration and angiogenesis in vitro. In an in vivo diabetic wound model, using rats, the DMN@TH/rh-EGF patch is able to inhibit inflammation, promote angiogenesis, collagen deposition, and tissue regeneration during the wound healing process, promoting its healing.