Production of Plant-Based, Film-Type Scaffolds Using Alginate and Corn Starch for the Culture of Bovine Myoblasts.

Natural scaffolds have been the cornerstone of tissue engineering for decades, providing ideal environments for cell growth within extracellular matrices. Previous studies have favored animal-derived materials, including collagen, gelatin, and laminin, owing to their superior effects in promoting cell attachment, proliferation, and differentiation compared to non-animal scaffolds, and used immortalized cell lines. However, for cultured meat production, non-animal-derived scaffolds with edible cells are preferred. Our study represents the first research to describe plant-derived, film-type scaffolds to overcome limitations associated with previously reported thick, gel-type scaffolds completely devoid of animal-derived materials. This approach has been employed to address the difficulties of fostering bovine muscle cell survival, migration, and differentiation in three-dimensional co-cultures. Primary bovine myoblasts from Bos Taurus Coreanae were harvested and seeded on alginate (Algi) or corn-derived alginate (AlgiC) scaffolds. Scaffold functionalities, including biocompatibility and the promotion of cell proliferation and differentiation, were evaluated using cell viability assays, immunofluorescence staining, and reverse transcription-quantitative polymerase chain reaction. Our results reveal a statistically significant 71.7% decrease in production time using film-type scaffolds relative to that for gel-type scaffolds, which can be maintained for up to 7 days. Film-type scaffolds enhanced initial cell attachment owing to their flatness and thinness relative to gel-type scaffolds. Algi and AlgiC film-type scaffolds both demonstrated low cytotoxicity over seven days of cell culture. Our findings indicated that PAX7 expression increased 16.5-fold in alginate scaffolds and 22.8-fold in AlgiC from day 1 to day 3. Moreover, at the differentiation stage on day 7, MHC expression was elevated 41.8-fold (Algi) and 32.7-fold (AlgiC), providing initial confirmation of the differentiation potential of bovine muscle cells. These findings suggest that both Algi and AlgiC film scaffolds are advantageous for cultured meat production.

Chitosan Nanoparticles-Based Cancer Drug Delivery: Application and Challenges.

Chitin is the second most abundant biopolymer consisting of N-acetylglucosamine units and is primarily derived from the shells of marine crustaceans and the cell walls of organisms (such as bacteria, fungi, and algae). Being a biopolymer, its materialistic properties, such as biodegradability, and biocompatibility, make it a suitable choice for biomedical applications. Similarly, its deacetylated derivative, chitosan, exhibits similar biocompatibility and biodegradability properties, making it a suitable support material for biomedical applications. Furthermore, it has intrinsic material properties such as antioxidant, antibacterial, and antitumor. Population studies have projected nearly 12 million cancer patients across the globe, where most will be suffering from solid tumors. One of the shortcomings of potent anticancer drugs is finding a suitable cellular delivery material or system. Therefore, identifying new drug carriers to achieve effective anticancer therapy is becoming essential. This paper focuses on the strategies implemented using chitin and chitosan biopolymers in drug delivery for cancer treatment.

pH Sensitive Drug Delivery Behavior of Palmyra Palm Kernel Hydrogel of Chemotherapeutic Agent.

This study examined the gel behavior of naturally-occurring palmyra palm kernel (PPK). Due to the presence of polysaccharide in PPK hydrogels, they exhibit excellent swelling behavior in response to pH. Chemotherapeutic drug 5-fluorouracil (5-FU) was encapsulated in these gels using an equilibrium swelling technique. It was found that 5-FU had an encapsulation efficiency of up to 62%. To demonstrate the drug stability in the gels, the PPK hydrogels were characterized using fourier transform infrared spectroscopy, differential scanning calorimetry, and X-ray diffraction. The results showed that the PPK hydrogel matrix contained molecularly dispersed 5-FU drug. The PPK hydrogel exhibited a denser structure and a rough surface, according to images obtained by scanning electron microscopy. In vitro release tests were carried out at pH 1.2 (gastric fluid) and 7.4 (intestinal fluid). The efficacy of the encapsulation and the release patterns were influenced by the network topology of the PPK hydrogel. The release patterns showed that 5-FU was released gradually over a time internal of more than 12 h. The findings suggest that naturally-occurring PPK hydrogels loaded with chemotherapeutic drugs could be employed to treat colon cancer.

Triple-Networked Hybrid Hydrogels Reinforced with Montmorillonite Clay and Graphene Nanoplatelets for Soft and Hard Tissue Regeneration.

Hydrogel is a three-dimensional (3D) soft and highly hydrophilic, polymeric network that can swell in water and imbibe a high amount of water or biological fluids. Hydrogels have been used widely in various biomedical applications. Hydrogel may provide a fluidic tissue-like 3D microenvironment by maintaining the original network for tissue engineering. However, their low mechanical performances limit their broad applicability in various functional tissues. This property causes substantial challenges in designing and preparing strong hydrogel networks. Therefore, we report the triple-networked hybrid hydrogel network with enhanced mechanical properties by incorporating dual-crosslinking and nanofillers (e.g., montmorillonite (MMT), graphene nanoplatelets (GNPs)). In this study, we prepared hybrid hydrogels composed of polyacrylamide, poly (vinyl alcohol), sodium alginate, MMT, and MMT/GNPs through dynamic crosslinking. The freeze-dried hybrid hydrogels showed good 3D porous architecture. The results exhibited a magnificent porous structure, interconnected pore-network surface morphology, enhanced mechanical properties, and cellular activity of hybrid hydrogels.

Childhood Obesity: A Potential Key Factor in the Development of Glioblastoma Multiforme.

Glioblastoma multiforme (GBM) is a malignant primary tumor type of the central nervous system (CNS). This type of brain tumor is rare and is responsible for 12-15% of all brain tumors. The typical survival rate of GBM is only 12 to 14 months. GBM has a poor and unsatisfactory prognosis despite advances in research and therapeutic interventions via neurosurgery, radiation, and chemotherapy. The molecular heterogeneity, aggressive nature, and occurrence of drug-resistant cancer stem cells in GB restricts the therapeutic efficacy. Interestingly, the CNS tumors in children are the second most usual and persistent type of solid tumor. Since numerous research studies has shown the association between obesity and cancer, childhood obesity is one of the potential reasons behind the development of CNS tumors, including GBM. Obesity in children has almost reached epidemic rates in both developed and developing countries, harming children's physical and mental health. Obese children are more likely to face obesity as adults and develop non-communicable diseases such as diabetes and cardiovascular disease as compared to adults with normal weight. However, the actual origin and cause of obesity are difficult to be pointed out, as it is assumed to be a disorder with numerous causes such as environmental factors, lifestyle, and cultural background. In this narrative review article, we discuss the various molecular and genetic drivers of obesity that can be targeted as potential contributing factors to fight the development of GBM in children.

Revised Manuscript with Corrections: Polyurethane-Based Conductive Composites: From Synthesis to Applications.

The purpose of this review article is to outline the extended applications of polyurethane (PU)-based nanocomposites incorporated with conductive polymeric particles as well as to condense an outline on the chemistry and fabrication of polyurethanes (PUs). Additionally, we discuss related research trends of PU-based conducting materials for EMI shielding, sensors, coating, films, and foams, in particular those from the past 10 years. PU is generally an electrical insulator and behaves as a dielectric material. The electrical conductivity of PU is imparted by the addition of metal nanoparticles, and increases with the enhancing aspect ratio and ordering in structure, as happens in the case of conducting polymer fibrils or reduced graphene oxide (rGO). Nanocomposites with good electrical conductivity exhibit noticeable changes based on the remarkable electric properties of nanomaterials such as graphene, RGO, and multi-walled carbon nanotubes (MWCNTs). Recently, conducting polymers, including PANI, PPY, PTh, and their derivatives, have been popularly engaged as incorporated fillers into PU substrates. This review also discusses additional challenges and future-oriented perspectives combined with here-and-now practicableness.

Efficacy of Bacterial Nanocellulose in Hard Tissue Regeneration: A Review.

Bacterial nanocellulose (BNC, as exopolysaccharide) synthesized by some specific bacteria strains is a fascinating biopolymer composed of the three-dimensional pure cellulosic nanofibrous matrix without containing lignin, hemicellulose, pectin, and other impurities as in plant-based cellulose. Due to its excellent biocompatibility (in vitro and in vivo), high water-holding capacity, flexibility, high mechanical properties, and a large number of hydroxyl groups that are most similar characteristics of native tissues, BNC has shown great potential in tissue engineering applications. This review focuses on and discusses the efficacy of BNC- or BNC-based biomaterials for hard tissue regeneration. In this review, we provide brief information on the key aspects of synthesis and properties of BNC, including solubility, biodegradability, thermal stability, antimicrobial ability, toxicity, and cellular response. Further, modification approaches are discussed briefly to improve the properties of BNC or BNC-based structures. In addition, various biomaterials by using BNC (as sacrificial template or matrix) or BNC in conjugation with polymers and/or fillers are reviewed and discussed for dental and bone tissue engineering applications. Moreover, the conclusion with perspective for future research directions of using BNC for hard tissue regeneration is briefly discussed.

Properties of Silicone Rubber-Based Composites Reinforced with Few-Layer Graphene and Iron Oxide or Titanium Dioxide.

The increasing demand for polymer composites with novel or improved properties requires novel fillers. To meet the challenges posed, nanofillers such as graphene, carbon nanotubes, and titanium dioxide (TiO2) have been used. In the present work, few-layer graphene (FLG) and iron oxide (Fe3O4) or TiO2 were used as fillers in a room-temperature-vulcanized (RTV) silicone rubber (SR) matrix. Composites were prepared by mixing RTV-SR with nanofillers and then kept for vulcanization at room temperature for 24 h. The RTV-SR composites obtained were characterized with respect to their mechanical, actuation, and magnetic properties. Fourier-transform infrared spectroscopy (FTIR) analysis was performed to investigate the composite raw materials and finished composites, and X-ray photoelectron spectroscopy (XPS) analysis was used to study composite surface elemental compositions. Results showed that mechanical properties were improved by adding fillers, and actuation displacements were dependent on the type of nanofiller used and the applied voltage. Magnetic stress-relaxation also increased with filler amount and stress-relaxation rates decreased when a magnetic field was applied parallel to the deformation axes. Thus, this study showed that the inclusion of iron oxide (Fe3O4) or TiO2 fillers in RTV-SR improves mechanical, actuation, and magnetic properties.

Preparation of Waterborne Polyurethane-Based Macroporous Sponges as Wound Dressings.

Recently, eco-friendly and biologically harmless products of waterborne polyurethane (WPU) instead of solvent-borne polyurethane have been strongly progressed in both industries and research areas. Accordingly, we developed a WPU-based macroporous sponge as a skin tissue engineering matrix. Also, the WPU dispersion in water was modified by using a foaming agent in order to create creamy emulsion resulting in enlarging surface area wherein cells could adhere, grow, and proliferate. We investigated the effect of a foaming agent on the morphology of surface and internal structure, wettability. In vitro studies also confirmed enhanced adherence and proliferation of cells with increased metabolic rate. These results proved that the use of foaming agent could alter the internal structure, surface property, and biocompatibility.

Synthesis and Characterization of Carboxymethyl Chitosan Scaffolds Grafted with Waterborne Polyurethane.

Bone tissue engineering has been rapidly developed in regenerative medicine field, which aims to induce new functional bone regeneration through the synergistic combination of biomaterials and cells. Porous biomaterials with sufficient mechanical properties and functional impregnating for bone substitutes have been imposed in the oncoming generation of bone reconstruction. In this study, we fabricated Carboxymethyl chitosan three dimensional (3D) porous scaffold modified with waterborne polyurethane (WPU) through freeze drying technique. In order to check its potential in bone tissue substitutes, osteoblast cells (hFOB 1.19) were seeded onto the fabricated scaffolds and then, SEM and proliferation assay were performed. The enhanced proliferation was contributed to 3D macroporous network structure, large surface area, and osteoconductive environments.

Image Segmentation for FIB-SEM Serial Sectioning of a Si/C-Graphite Composite Anode Microstructure Based on Preprocessing and Global Thresholding.

The choice of materials that constitute electrodes and the way they are interconnected, i.e., the microstructure, influences the performance of lithium-ion batteries. For batteries with high energy and power densities, the microstructure of the electrodes must be controlled during their manufacturing process. Moreover, understanding the microstructure helps in designing a high-performance, yet low-cost battery. In this study, we propose a systematic algorithm workflow for the images of the microstructure of anodes obtained from a focused ion beam scanning electron microscope (FIB-SEM). Here, we discuss the typical issues that arise in the raw FIB-SEM images and the corresponding preprocessing methods that resolve them. Next, we propose a Fourier transform-based filter that effectively reduces curtain artifacts. Also, we propose a simple, yet an effective, global-thresholding method to identify active materials and pores in the microstructure. Finally, we reconstruct the three-dimensional structures by concatenating the segmented images. The whole algorithm workflow used in this study is not fully automated and requires user interactions such as choosing the values of parameters and removing shine-through artifacts manually. However, it should be emphasized that the proposed global-thresholding method is deterministic and stable, which results in high segmentation performance for all sectioning images.

Nanoscale Electrical Degradation of Silicon-Carbon Composite Anode Materials for Lithium-Ion Batteries.

High-performance lithium-ion batteries (LIBs) are in increasing demand for a variety of applications in rapidly growing energy-related fields including electric vehicles. To develop high-performance LIBs, it is necessary to comprehensively understand the degradation mechanism of the LIB electrodes. From this viewpoint, it is crucial to investigate how the electrical properties of LIB electrodes change under charging and discharging. Here, we probe the local electrical properties of LIB electrodes with nanoscale resolution by scanning spreading resistance microscopy (SSRM). Via quantitative and comparative SSRM measurements on pristine and degraded LIB anodes of Si-C composites blended with graphite (Gr) particles, the electrical degradation of the LIB anodes is visualized. The electrical conductivity of the Si-C composite particles considerably degraded over 300 cycles of charging and discharging, whereas the Gr particles maintained their conductivity.

Protective Oxide Coating for Ionic Conductive Solid Electrolyte Interphase.

To employ Li-based batteries to their full potential in a wide range of energy-storage applications, their capacity and performance stability must be improved. Si is a viable anode material for Li-based batteries in electric vehicles due to its high theoretical capacity and good economic feasibility. However, it suffers from physical and chemical degradation, leading to unstable electrochemical performance and preventing its incorporation in new Li-based battery systems. Herein, we applied a poly(vinyl alcohol)-PO4 protective coating for Si-graphite anodes and confirmed an improvement in the electrochemical performance. The experimental results revealed that the polymer acts as a binder to alleviate the pulverization of the electrode. Furthermore, the oxide coating reduces the loss of Li2O, which has high ionic conductivity, during operation, resulting in the formation of a stable solid electrolyte interphase. Our findings suggest that a stable and ion-conducting anode/interphase can be developed by applying an oxide and polymer coating in combined approach. Therefore, this study is expected to provide a basis for the further development and design of high-performance Li-based battery systems.

Evaluation of poly (aspartic acid sodium salt) as a draw solute for forward osmosis.

Poly (aspartic acid sodium salt) (PAspNa) was evaluated for its potential as a novel draw solute in forward osmosis (FO). The inherent advantages of PAspNa, such as good water solubility, high osmotic pressure, and nontoxicity, were first examined through a series of physicochemical analyses and atomic-scale molecular dynamics simulations. Then, lab-scale FO tests were performed to evaluate its suitability in practical processes. Compared to other conventional inorganic solutes, PAspNa showed comparable water flux but significantly lower reverse solute flux, demonstrating its suitability as a draw solute. Moreover, fouling experiments using synthetic wastewater as a feed solution demonstrated that PAspNa reversely flowed to the feed side reduced inorganic scaling on the membrane active layer. The recyclability of PAspNa was studied using both nanofiltration (NF) and membrane distillation (MD) processes, and the results exhibited its ease of recovery. This research reported the feasibility and applicability of FO-NF or FO-MD processes using PAspNa for wastewater reclamation and brackish water desalination.

Multiscale porous interconnected nanocolander network with tunable transport properties.

A nanocolander network is developed by embedding mesoporous block copolymers inside the structural frame of a macroporous inverse-opal structure. Spontaneously formed macroconduits interconnecting the macropores are utilized as internal bypasses for enhancing the bulk transport properties. A demonstrative application for the membrane of the nanocolander network is of perfect size-selectivity for nanoparticle separation without compromising the high permeability of the transporting medium.

Particle-nested inverse opal structures as hierarchically structured large-scale membranes with tunable separation properties.

A novel multiscale porous architecture where an individual particle is nested inside a hollow chamber of inverse-opal (IO) frame is created using a large scale self-assembly of core-shell structured colloidal particles and subsequent selective removal of the outer shells of the colloids. Since the nested particle is smaller than the size of individual IO chamber, the interconnected nanochannels are spontaneously formed within the structured frame. The size of internal nanochannels is readily tuned to have high permeability and size-selective separation capability, which is successfully tested for nanoparticle separation.

Dynamics of dilute solutions of poly(aspartic acid) and its sodium salt elucidated from atomistic molecular dynamics simulations with explicit water.

The use of forward osmosis (FO) process for seawater desalination has attracted tremendous interest in recent years. Besides the manufacture of suitable membranes, the major technical challenge in the efficient deployment of the FO technology lies in the development of a suitable "draw solute". Owing to its inherent advantages, poly(aspartic acid) has arisen to be an attractive candidate for this purpose. However, an investigation of its molecular level properties has not been studied in detail. In this paper, the dynamics of poly(aspartic acid) and its sodium salt in the dilute concentration regime have been reported. The quantification of the polymer conformational properties, its solvation behavior, and the counterion dynamics are studied. The neutral polymer shows a preferentially coiled structure whereas the fully ionized polymer has an extended structure. Upon comparing with poly(acrylic acid) polymer, another polymer which has been used as a draw solute, poly(aspartic acid) forms more number of hydrogen bonds as well as fewer ion pairs.

Dual effective organic/inorganic hybrid star-shaped polymer coatings on ultrafiltration membrane for bio- and oil-fouling resistance.

Amphiphilic organic/inorganic hybrid star-shaped polymers (SPP) were prepared by atom transfer radical polymerization (ATRP) using poly(ethylene glycol) methyl ether methacrylate (PEGMA) and 3-(3,5,7,9,11,13,15-heptacyclohexyl-pentacyclo[9.5.1.1³,9.15,¹5.17,¹³]-octasiloxane-1-yl)propyl methacrylate (MA-POSS) as monomers and octakis(2-bromo-2-methylpropionoxypropyldimethylsiloxy)-octasilsesquioxane (OBPS) as an initiator. Star-shaped polymers (SPM) having PEGMA and methyl methacrylate (MMA) moieties were also prepared for comparative purposes. Polysulfone (PSf) ultrafiltration membranes coated with the SPP showed higher bio- and oil-fouling resistance and flux-recovery ability than the bare PSf membrane. Moreover, the SPP-coated membranes exhibited better antifouling properties than the SPM-coated membrane when they were used for oil/water emulsion filtration. The dual effective antifouling properties of the SPP were ascribed to the simultaneous enrichment of hydrophilic PEG and hydrophobic POSS moieties on the membrane surfaces resulting in the decrease in interactions with proteins and the increase in repellence to oils.

Layer-by-layer assembly of polyelectrolyte multilayers in three-dimensional inverse opal structured templates.

A novel means of layer-by-layer deposition (LbL) of polyelectrolyte multilayers on three-dimensionally porous inverse opal (3D-IO) structures is presented. The 3D-IO structures comprising UV-curable polymer are highly flexible and can be readily demonstrated as free-standing films with double-sided open porosity over a large scale. A conflict between the intrinsically hydrophobic polymeric structures and waterborne characteristics of the LbL deposition process is overcome by employing a mixed solvent system of water and alcohol. The deposition pH of the LbL assembly can strongly affect the charge density and the degree of entanglement of polyelectrolyte chains, resulting in contrastingly different film deposition and growth behaviors. Since this method utilizes a three-dimensionally structured surface as a deposition substrate, 3D-IO films with a thickness of tens of micrometers can be uniformly and completely deposited with polyelectrolyte multilayers using only several tens of bilayer depositions, which can offer a new pathway of fabricating functionalized polymeric films. Finally, the LbL treated 3D-IO films are applied to nanofiltration membranes for removing multivalent metallic cations. Due to the enhanced Donnan exclusion effect as a result of multiple interfaces formed inside the 3D-IO structures and the relatively large volumetric ratio of water-permeable polyelectrolyte complexes, outstanding membrane performance was observed. Specifically, a good rejection rate of metal ions was achieved even under highly diluted feed conditions without sacrificing the high permeation flux.