Induced Phase Separation Research Articles

Substrate-induced condensation activates plant TIR domain proteins

Plant nucleotide-binding leucine-rich repeat (NLR) immune receptors with an N-terminal Toll/interleukin-1 receptor (TIR) domain mediate recognition of strain-specific pathogen effectors, typically via their C-terminal ligand-sensing domains1. Effector binding enables TIR-encoded enzymatic activities that are required for TIR–NLR (TNL)-mediated immunity2,3. Many truncated TNL proteins lack effector-sensing domains but retain similar enzymatic and immune activities4,5. The mechanism underlying the activation of these TIR domain proteins remain unclear. Here we show that binding of the TIR substrates NAD+ and ATP induces phase separation of TIR domain proteins in vitro. A similar condensation occurs with a TIR domain protein expressed via its native promoter in response to pathogen inoculation in planta. The formation of TIR condensates is mediated by conserved self-association interfaces and a predicted intrinsically disordered loop region of TIRs. Mutations that disrupt TIR condensates impair the cell death activity of TIR domain proteins. Our data reveal phase separation as a mechanism for the activation of TIR domain proteins and provide insight into substrate-induced autonomous activation of TIR signalling to confer plant immunity.

Thermally induced phase separation PVDF membrane fabricated by using NaCl coagulation bath: Relation of membrane surface morphology and permeation performance

Efforts have been made in thermally induced phase separation (TIPS) process to modify the morphology of polyvinylidene fluoride (PVDF) membranes in order to improve their permeation performance and mechanical properties. Nevertheless, many methods not only altered the outer surface but also impacted the overall membrane structure, resulting in a trade-off between permeability and mechanical properties. In this study, we utilized a modified TIPS process to refine the outer surface morphology without altering the bulk structure. This was achieved by introducing NaCl in the coagulation bath. The PVDF membranes were fabricated using a dope with water insoluble diluent dimethyl phthalate (DMP) as main solvent and water-soluble additives polyethylene glycol 400 (PEG400)/triethylene glycol (TEG) as pore formers. The inclusion of NaCl in the coagulation bath serves to decrease the solubility of PEG within this medium, owing to the salting-out effect. Consequently, the NaCl concentration in the coagulation bath emerges as a crucial factor in regulating the migration of PEG400 toward the membrane surface. This control mechanism facilitates the precise adjustment of the outer surface morphology in the fabrication of membranes. As the NaCl concentration increases in the coagulation bath, the outer surface of the fabricated membrane transited from a mesh-like structure to a spherulite structure. As 0.5 mol L−1 NaCl was added to the coagulation bath, the membranes displayed a pure water permeability of 1073.9 L m−2 h−1 bar−1 while maintaining a narrow pore size distribution. Compared to the membranes fabricated without NaCl addition, the increment of the PWP contributed to the slight increase in mean pore size from 65 nm to 84 nm. Meanwhile, the water-insoluble diluent DMP was not affected by the addition of NaCl, which means that the bulk structure of the membrane could be maintained. Consequently, the increase in permeability did not compromise the mechanical properties of the membranes. All the membranes fabricated in this study maintained a reasonable tensile strength of approximately 3 MPa. This study introduces a simple and environmental method to increase the permeability effectively and fine-tune the pore size of the TIPS membranes while having little effect on the bulk structure. Furthermore, the study provides valuable insights into how changes in outer surface morphology can impact the pore size and permeability of TIPS PVDF membranes.

Biodegradable Honeycomb-Mimic Scaffolds Consisting of Nanofibrous Walls.

The scaffold is a porous three-dimensional (3D) material that supports cell growth and tissue regeneration. Such 3D structures should be generated with simple techniques and nontoxic ingredients to mimic bio-environment and facilitate tissue regeneration. In this work, simple but powerful techniques are demonstrated for the fabrication of lamellar and honeycomb-mimic scaffolds with poly(L-lactic acid). The honeycomb-mimic scaffolds with tunable pore size ranging from 70 to 160µm are fabricated by crystal needle-guided thermally induced phase separation in a directional freezing apparatus. The compressive modulus of the honeycomb-mimic scaffold is ≈4 times higher than that of scaffold with randomly oriented pore structure. The fabricated honeycomb-mimic scaffold exhibits a hierarchical structure from nanofibers to micro-/macro-tubular structures. Pre-osteoblast MC3T3-E1 cells cultured on the honeycomb-mimic nanofibrous scaffolds exhibit an enhanced osteoblastic phenotype, with elevated expression levels of osteogenic marker genes, than those on either porous lamellar scaffolds or porous scaffolds with randomly oriented pores. The advanced techniques for the fabrication of the honeycomb-mimic structure may potentially be used for a wide variety of advanced functional materials.

Development of novel high anti-pollution polyamide/polysulfate disk tubular reverse osmosis membrane modules and their application in simulated space bathing wastewater

Water is a precious resource in space stations, and wastewater recycling is necessary to meet the needs of astronauts. In that respect, applying the high anti-pollution disk tubular reverse osmosis (DTRO) technique is a reliable way to remove pollutes from wastewater. Thin film composite (TFC) membrane treatment is the most frequently employed solution for purifying wastewater in industry; however, the intrinsic weaknesses of polymer membrane substrates, e.g., poor mechanical property, foulant adsorption and low resistance to acidic/basic conditions, greatly hamper their applications. In this study, the novel polysulfate (PSE) membrane substrates were prepared via non-solvent induced phase separation (NIPS) method. The microstructure and performance of PSE membrane substrates were comprehensively investigated at varying polymer concentration and nanoparticle types. The results showed that adding nanosilver to the support layer significantly enhanced the TFC- PSE/Ag membrane performance (up to 57 %) and tensile strength (by 4.57 ± 0.13). According to computational fluid dynamics (CFD) simulations, the optimized geometric design of deflectors would have noticeably improved the flow field distribution and strength, which was consistent with experimental data. The DTRO modules enabled the effective management of wastewater using simulated space bathing wastewater. The effluent met the water reuse criteria in terms of COD concentration, NH3-N concentration, conductivity and turbidity whose respective values were 15 mg/L, 0.21 mg/L, 60 μS/cm, and 0.9 NTU. The proposed DTRO modules own antifouling and acid/alkaline-resistance, indicating their remarkable application potential in the large-scale recovery of bathing wastewater from the earth or space station.

Facile fabrication of polystyrene/lignin /OV-POSS nanocomposite monolith by thermally induced phase separation method for wastewater cleanup

Facile fabrication of polystyrene/lignin /OV-POSS nanocomposite monolith by thermally induced phase separation method for wastewater cleanup

Nonsolvent-induced electrospun fibers with crater-like surface and high-loading polytriphenylamine-derived as a flexible cathode for lithium-ion batteries

Fabricating electrodes simultaneously possessing remarkable flexibility, excellent mechanical properties, and high energy density remains a significant challenge in flexible lithium-ion batteries (LIBs). Herein, a series of flexible organic composite films were prepared with high-loading polytriphenylamine (PTPA) and the derivative (PTPA-PO) as active material, along with carbon nanotubes (CNTs) serving as conductive filler. The fabrication employed the polyethylene oxide (PEO) assisted nonsolvent (or poor solvent) induced phase separation electrospinning (NIPSE) method. Subsequently, the fiber morphology and electrochemical applications of the flexible organic composite films were systematically studied. Notably, the 60 % PTPA-PO/20 % CNTs/PEO flexible electrode with a high-loading active material of 60 wt% exhibits a significant discharge capacity of 146.6 mAh·g−1 and a favorable discharge platform ∼ 3.7 V vs. Li. Furthermore, the inherent flexibility of electrode contributes to efficient and stable transport of ions and electrons, resulting in a fine capacity retention of 93.3 % after 100 cycles. The improvement of electrochemical performance can be rationalized by the unique internal conductive network and crater-like surface structure of the fibers formed through the NIPSE method. This work provides an efficient method to fundamentally improve the energy storage performance and flexibility of LIBs.

Effect of annealing on the morphology and properties of poly(lactic acid)/polyhedral oligomeric silsesquioxane asymmetric porous membranes prepared through non‐solvent induced phase separation and its application

AbstractNon‐solvent induced phase separation (NIPS) method was employed to fabricate biodegradable poly(lactic acid) (PLA) nanocomposite membranes. Morphological studies using scanning electron microscopy revealed that all the membranes prepared display asymmetric structures comprising finger‐like macropores. The incorporation of modified polyhedral oligomeric silsesquioxane (POSS) particles into the PLA matrix resulted in enhanced crystallinity, mechanical, and thermal properties. Annealing of the membranes was performed to explore the influence of temperature on the morphology and properties. After annealing, membranes become more thin and compact, and drastic enhancement in crystallinity is also observed. Consequently, Young's modulus experiences a significant improvement. The reduction in oil absorption capacity after annealing can be attributed to the higher level of crystallinity, reduced porosity, and smaller pore diameter observed in the annealed membranes. Additionally, the unannealed PLA nanocomposite membranes demonstrated exceptional oil absorption capacity, reaching approximately 88%. It is foreseeable that these PLA/POSS nanocomposite membranes possess the potential to be utilized as effective tools for oil–water separation, offering the advantage of mitigating secondary pollution.

Effect of thermal processing conditions on the structure and properties of porous PENK/PVDF composite films and its application as lithium-ions separators

By developing high-performance lithium-ion battery technology, the demands on the design of separator modification have increased. However, battery performance and safety are limited by conventional polyolefin separators' poor thermal resistance and electrolyte wettability. Biphenyl-type poly (arylene ether nitrile ketone) (BP-PENK) is synthesized. PENK polymers are a class of poly (aryl ether) with excellent properties of both Poly (aryl ether nitrile) (PEN) and Poly (ether ketone) (PEEK). The BP-PENK/PVDF composite film is further processed by non-solvent induced phase separation (NIPS), and the impact of annealing temperatures on the thermal resistance and crystalline phase structure of composite separators has been studied. The composite separator owns enhanced ionic conductivity, excellent electrolyte wettability, and superior thermal durability. The cell equipped with the composite separator has a discharge-specific capacity of 146.5 mAh·g−1 and a capacity retention rate of 86.64 %. In this way, A novel approach to producing lithium-ion battery separators that possess outstanding electrochemical properties and high thermal durability is provided.

Preparation and performance of magnetic carbon nanotubes modified PVC substrate composite nanofiltration membranes

Polyamide (PA)/ferroferric oxide/oxidized multi-walled carbon nanotubes (Fe3O4/o-MWCNTs)/polyvinyl chloride (PVC) composite nanofiltration (NF) membranes were prepared by the interfacial polymerization (IP) process with the Fe3O4/o-MWCNTs/PVC porous membrane as the substrate membrane, which was prepared by the magnetic field assisted non-solvent induced phase separation method (NIPS) with the synthesized superparamagnetic Fe3O4/o-MWCNTs nanoparticles (NPs) as the additives of the functional intermediate layer integrated with the substrate. The effects of the magnetic carbon nanotubes modified PVC porous substrate membrane on the surface chargeability, PA layer thickness, mechanical properties, pressure resistance and permeability of the composite NF membranes were investigated, and the comprehensive performance of composite NF membranes was enhanced. The results indicated that the porosity and hydrophilicity of the Fe3O4/o-MWCNTs/PVC porous substrate membrane were improved by the migration of magnetic Fe3O4/o-MWCNTs NPs to the upper edge of the substrate membrane and uniform enrichment under magnetic field induction, which further affected the structure and properties of the PA/Fe3O4/o-MWCNTs/PVC composite NF membrane. The prepared NF membrane presented smaller roughness, thinner PA layer, larger pore size, with excellent mechanical properties and better pressure resistance. Meanwhile, the PA/Fe3O4/o-MWCNTs/PVC composite NF membrane presented excellent divalent salt rejection, with the rejection of MgSO4 and Na2SO4 maintaining more than 95.2% and 93.4%, respectively, while the permeation flux could reach 35.4 L·m−2·h−1. In summary, the modification of the substrate integrated with the functional intermediate layer had certain enlightening significance for the preparation of the NF membrane with excellent comprehensive performance.

Investigating the Role of a P(VDF−TrFE) Ferroelectric Separator in Li‐Metal Pouch Cells using Electrochemical Impedance Spectroscopy

AbstractThis study explores the efficacy of employing P(VDF−TrFE), a ferroelectric copolymer, to mitigate the formation of dead lithium in Li‐metal anodes when paired with carbonate electrolytes. Employing non‐solvent induced phase separation (NIPS), self‐standing membranes and coatings on polypropylene (PP) separators were prepared, both demonstrating a homogenous cellular pore structure and excellent ionic conductivity. Rigorous evaluation in pouch cell formats, featuring a thin Li‐metal anode (50 μm), a high‐loading NMC532 cathode (3 mAhcm−2), and a carbonate electrolyte, reveals the superior performance of cells with P(VDF−TrFE)‐coated PP separators. Notably, these cells exhibit slower and more consistent capacity fading, as well as the weakest increase in impedance, as evidenced by Electrochemical Impedance Spectroscopy (EIS) investigations. This work underscores the promising role of P(VDF−TrFE) as a key material for addressing challenges associated with dead lithium, offering valuable insights for advancing Li‐metal battery technologies in practical applications.

Stereo-complex polylactide composite aerogel for crude oil adsorption

Adsorption materials are a cost-effective and simple method for oil spill remediation, but their efficiency is limited by high crude oil viscosity. Additionally, non-degradable materials pose another risk of secondary pollution, such as microplastic debris. Here, an environmentally-friendly stereo-complex polylactide composite (SCC) aerogel were developed via water-assisted thermally induced phase separation. The SCC with 3 wt% carbon nanotubes had a hierarchical structure of micro/nanoscale pores and high content of stereo-complex crystallites (35.7 %). Along with the excellent water repellency (water contact angle: 157°), SCC aerogel was 2.7 times as resistant to hydrolysis than poly(l-lactide) aerogel (Ph = 13, 37 °C). Additionally, a maximum absorption capacity of 41.2 g g−1 and over 97 % oil/water separation efficiency after 10 cycles were obtained in low viscosity conditions; while in high viscosity conditions, it displayed excellent photothermal performance, reaching a surface temperature of 85 °C under 1 sunlight, reducing crude oil absorption time from 42 min to 60 s (97.6 %-time savings). Moreover, it facilitated continuous crude oil spill recovery under sunlight with an adsorption rate of 3.3 × 104 kg m−3 h−1. The SCC aerogel presents a potential route for utilizing solar energy in crude oil adsorption applications without additional environmental burden.

Influence of citric acid concentrations on the porosity and performance of cellulose acetate-based porous membranes: A comprehensive study

This study investigates the influence of citric acid concentration on the fabrication of porous cellulose acetate (CA) membranes using the Non-Solvent Induced Phase Separation (NIPS) method. A notable aspect is the precise control over membrane properties, particularly pore size and porosity, achieved solely through the adjustment of citric acid concentration, serving as the additive. Higher concentrations of citric acid increase pore size by rendering polymer chains more pliable, whereas lower concentrations lead to smaller, denser pores due to improved dispersion in the CA matrix and altered water interactions during phase separation. A decrease in porosity and Gurley values with reducing citric acid concentrations (from 5 × 10−2 to 1 × 10−3 M ratios) indicates less plasticization of CA chains. However, at very low concentrations (1 × 10−4 and 1 × 10−5), porosity increases, despite the presence of smaller pores, and Gurley values approach those of pure CA in terms of gas permeability. Fourier Transform Infrared (FT-IR) spectroscopy confirms the presence of citric acid and its interaction with carbonyl groups, consistent with the pore size observations from Scanning Electron Microscopy (SEM). Spectral data deconvolution reveals weakened carbonyl bonds due to the reduced presence of citric acid, correlating with the smaller pores observed in SEM. Thermal Gravimetric Analysis (TGA) demonstrates that composite membranes are more thermally stable than pure CA, attributed to the citric acid-induced crosslinking within the polymer chains. Stability increases with decreasing citric acid concentration, with some anomalies at the lowest levels. In conclusion, this study highlights the capability of adjusting citric acid concentration to tailor membrane properties, offering valuable insights for the creation of porous materials across diverse industrial applications.

Fabrication of Polysulfone - Zeolite Nanocomposite Membrane for Water and Wastewater Treatment Applications

Freshwater is essential in sustaining human life on the planet and the demand for potable water has increased for the past years due to population growth and modernization. However, the natural resources of water have become polluted/contaminated due to industrialization and other human activities. The development of membrane technology, especially with the creation of nanocomposite materials, provides a solution to treat polluted or contaminated water through various separation processes resulting in the production of clean water fit for human consumption. In this study, polysulfone was added with zeolite nanoparticles to fabricate nanocomposite membranes via non-solvent induced phase separation (NIPS) method to enhance the hydrophilicity and mechanical strength of the membrane suitable for water and wastewater applications. The nanozeolite was added in varying concentrations; 1% 5% and 10% and the fabricated membranes were characterized via Contact Angle Goniometer, universal testing machine (UTM) and scanning electron microscopy (SEM) to determine the contact angle, tensile strength, and surface morphology, respectively. Based on the characterization data, the 1% concentration showed the highest tensile strength and the lowest contact angle measurement. The 1% nanozeolite concentration is the optimum membrane formulation due to the enhanced hydrophilicity and mechanical strength of the material.

Upcycled PVC support layer from waste PVC pipe for thin film composite nanofiltration membranes

Thin-film-composite (TFC) nanofiltration membranes represent the pinnacle of membrane technology in water treatment and desalination. These membranes typically consist of a polyamide (PA) selective layer and a membrane support layer, often constructed from commercially available materials like polyethersulfone (PES). However, there exists an alternative approach that involves the use of different polymers, preferably upcycled waste polymers, as a viable support layer for TFC membranes. Successfully implementing the upcycling of waste plastics into high-value support membranes can make a significant contribution to addressing the issue of plastic waste pollution. One of the primary challenges associated with utilizing upcycled polymers as support layers is the potential impact on the polyamide selective layer of TFC membranes, subsequently affecting their performance in terms of permeability, rejection, and antifouling properties. In this study, we demonstrate the successful fabrication of TFC membranes with a support layer crafted from upcycled waste PVC pipe. We conducted a comprehensive investigation into the effects of upcycled PVC on the structural and physicochemical properties of the polyamide layer. The ultrafiltration (UF) support membranes were fabricated from waste PVC pipe via the nonsolvent induced phase separation (NIPS) method. Subsequently, a polyamide layer was synthesized atop the Upcycled PVC membrane using interfacial polymerization (IP). The physicochemical properties and performance of the TFC membranes with upcycled PVC support layer were compared with membranes with research-grade (RG) PVC and commercial PES support layers. The results unveiled that the TFC membrane with upcycled PVC support layer exhibited higher water permeability (18.2 LMH/bar), in contrast to RG TFC (15.5 LMH/bar) and PES TFC membranes (13.7 LMH/bar). Furthermore, the salt rejection capabilities of the upcycled PVC TFC membrane were competitive and well within an acceptable range.

Sponge Inspired Flexible, Antibacterial Aerogel Electrode with Long‐Term High‐Quality Electrophysiological Signal Recording for Human‐Machine Interface

AbstractFlexible bioelectronics have a large range of applications in the field of human health monitoring and human‐machine interfaces. Among various bioelectronics, flexible electrodes have been widely studied. However, it is still lack of investigation in the development of electrodes with high signal quality and long service life. Here, a sponge inspired flexible electrode based on cellulose aerogel is developed via thermally induced phase separation. Due to its flexibility, the electrode can easily conform to skin and achieve a higher signal‐to‐noise ratio (SNR) than the commercial rigid electrode. At the same time, the aerogel electrode with a sponge‐like structure can absorb solutions several times their own weight (≈800%). In addition, the dope of polypyrrole coated silver nanowires (AgNWs@PPy) improves its intrinsic bactericidal activity (antibacterial rate above 97.8%) and the cellulose‐based material itself offers good skin compatibility. Therefore, all these features contribute to a longer service life, while has been proven in electrophysiological signals recording. The SNR of electrocardiogram (ECG) signals recorded by aerogel electrode in 24 h is ≈15% higher than that of commercial electrode. Apart from that, when the commercial electrode is unavailable for eye‐open (EO) and eye‐closed (EC) paradigm in 12 h, the aerogel electrode can still record clear electroencephalogram (EEG) features.

Enhanced antifouling and separation capabilities of polydopamine@Ce-MOF functionalized PES ultrafiltration membrane

The need for antifouling membranes is substantial due to fouling’s negative impact on the effectiveness and durability of ultrafiltration membranes. In recent times, Metal-Organic Frameworks (MOFs) have emerged as effective additives for crafting ultrafiltration (UF) membranes. However, to harness their benefits and mitigate their drawbacks, a well-considered approach is imperative. In this work, polyethersulfone (PES) UF membranes were tailored with polydopamine (PDA)-modified cerium (Ce)-MOF (PDA@Ce-MOF) to achieve satisfactory antifouling properties and to remove biological macromolecules such as bovine serum albumin (BSA) and humic acid (HA) from wastewater. The non-solvent induced phase separation (NIPS) method was used to simultaneously fabricate the membrane and modify it with different PDA@Ce-MOF concentrations ranging from 0.05 to 0.50 wt.%. Results showed significant improvements on the membrane’s morphology, hydrophilicity, porosity and pore size at 0.10 wt.% loading of PDA@Ce-MOF. The synergistic effect of the PDA and Ce-MOF on the membrane improved the pure water flux (337 L m−2 h−1) and filtration performance in the filtration of Bovine serum albumin (BSA) and humic acid (HA) reporting 145 L m−2 h−1 and 98% rejection, and 164 L m−2 h−1 and 88% rejection; respectively. Further, water-attracting functional moieties of PDA@Ce-MOF hindered the deposition of BSA protein on the membrane surface, resulting in an excellent flux recovery ratio (FRR) of ~87%, alongside mitigated irreversible fouling.

Atomistic Insight into the Lipid Nanodomains of Synaptic Vesicles.

Membrane curvature, once regarded as a passive consequence of membrane composition and cellular architecture, has been shown to actively modulate various properties of the cellular membrane. These changes could also lead to segregation of the constituents of the membrane, generating nanodomains with precise biological properties. Proteins often linked with neurodegeneration (e.g., tau, alpha-synuclein) exhibit an unintuitive affinity for synaptic vesicles in neurons, which are reported to lack distinct, ordered nanodomains based on their composition. In this study, all-atom molecular dynamics simulations are used to study a full-scale synaptic vesicle of realistic Gaussian curvature and its effect on the membrane dynamics and lipid nanodomain organization. Compelling indicators of nanodomain formation, from the perspective of composition, surface areas per lipid, order parameter, and domain lifetime, are identified in the vesicle membrane, which are absent in a flat bilayer of the same lipid composition. Therefore, our study supports the idea that curvature may induce phase separation in an otherwise fluid, disordered membrane.

Development of multifunctional membranes via plasma-assisted nonsolvent induced phase separation

Demands on superhydrophobic, self-cleaning and piezoelectric membranes have gained significantly due to their potential to overcome global shortages in clean water and energy. In this study, we have discovered a novel plasma-assisted nonsolvent induced phase separation (PANIPS) method to prepare superhydrophobic, self-cleaning and piezoelectric poly(vinylidene difluoride) (PVDF) membranes without additional chemical modifications or post-treatments. The PANIPS membranes exhibit water contact angles ranging from 151.2° to 166.4° and sliding angles between 6.7° and 29.7°. They also show a high piezoelectric coefficient (d33) of 10.5 pC N−1 and can generate a high output voltage of 10 Vpp. The PANIPS membranes can effectively recover pure water from various waste solutions containing Rose Bengal dye, humic acid, or sodium dodecyl sulfate via direct contact membrane distillation (DCMD). This study may provide valuable insights to fabricate PANIPS membranes and open up new avenues to molecularly design advanced superhydrophobic, self-cleaning, and piezoelectric membranes in the fields of clean water production, motion sensor, and piezoelectric nanogenerator.

Physically cross-linked scaffold composed of hydroxyapatite-chitosan-alginate-polyamide has potential to trigger bone regeneration in craniofacial defect

Abstract Recently, the fabrication of a scaffold from biomaterials has been increased due to the lack of adequate natural bone for grafting. In this study, hydroxyapatite-chitosan-alginate-polyamide (HCAP) synthetic scaffold was fabricated using the thermally induced phase separation (TIPS) technique. The scaffold was cross-linked with either a chemical cross-linker (calcium chloride, 2-hydroxyethyl methacrylate (HEMA), or glutaraldehyde (GTA)) or a physical cross-linker (gamma irradiation (IR)) resulting in scaffolds HCAP-CaCl2, HCAP-HEMA, HCAP-GTA, and HCAP-IR, respectively. The cross-linked scaffolds were characterized based on physicochemical properties, cytotoxicity, and biocompatibility. HCAP-GTA showed the highest density and the lowest swelling ratio and biodegradation rate closely matching with those of the HCAP-IR. Porosity and density of the HCAP, HCAP-IR, and HCAP-GTA scaffolds were 92.14, 87.26, and 83.33 %, and 0.241, 0.307, and 0.335 g/cm3, respectively. The swelling ratio for the same scaffolds was 149, 110, and 108 % after 72 h of observation. Brine shrimp cytotoxicity and RBC biocompatibility assay confirmed the non-toxic nature of HCAP-IR and HCAP-GTA scaffolds. The HCAP-IR scaffold was tested for bone regeneration in the rabbit mandible defect model. Histological analysis revealed the regeneration of new bone and restoration of bone defect at the site of injury. These findings indicate that radiation induced physically cross-linked HCAP scaffold could be used as an alternative in bone defect replacement therapy.

Preparation, Modification, and Application of Ethylene-Chlorotrifluoroethylene Copolymer Membranes.

Ethylene-chlorotrifluoroethylene (ECTFE) was first commercialized by DuPont in 1974. Its unique chemical structure gives it high heat resistance, mechanical strength, and corrosion resistance. But also due to these properties, it is difficult to prepare a membrane from it by the nonsolvent-induced phase separation (NIPS) method. However, it can be prepared as a microfiltration membrane using the thermally induced phase separation (TIPS) method at certain temperatures and with the selection of suitable solvents, and the use of green solvents is receiving increasing attention from researchers. The surface wettability of ECTFE membranes usually needs to be modified before use to strengthen its performance to meet the application requirements, usually by graft modification and surface oxidation techniques. This paper provides an overview of the structure of ECTFE and its preparation and modification methods, as well as recent advances in its application areas and prospects for the future methods of preparing high-performance ECTFE membranes.