Action of microbial transglutaminase (MTGase) on the processing properties of glutinous rice flour and the quality attributes of sweet dumplings and in vitro digestion.

The development and manufacture of high-quality starch are a new research focus in food science. Here, transglutaminase was used in the wet processing of glutinous rice flour to prepare customized sweet dumplings. Transglutaminase (0.2 %) lowered protein loss in wet processing and reduced the crystallinity and viscosity of glutinous rice flour. Moreover, it lowered the cracking and cooking loss of sweet dumplings after freeze-thaw cycles, and produced sweet dumplings with reduced hardness and viscosity, making them more suitable for people with swallowing difficulties. Additionally, in sweet dumplings with 0.2 % transglutaminase, the encapsulation of starch granules by the protein slowed down the digestion and reduced the final hydrolysis rate, which are beneficial for people with weight and glycemic control issues. In conclusion, this study contributes to the production of tasty, customized sweet dumplings.

Evaluation of perioperative pachymetry of thin corneas during corneal crosslinking using hypo-osmolar riboflavin and hydroxypropyl methylcellulose

ABSTRACT Purpose: This study aimed to analyze variations in intraoperative corneal thickness during corneal cross-linking in patients with keratoconus and to investigate its possible correlation with presurgical maximal keratometry (Kmax) and pachymetry. Methods: This was a prospective case series. We used a method similar to the Dresden protocol, with the application of hydroxypropyl methylcellulose 0.1% hypo-osmolar riboflavin in corneas between 330 and 400 µm after epithelium removal. Corneal thickness was measured using portable calipers before and immediately after epithelium removal, and 30 and 60 min after the procedure. Results: The 30 patients in this study were followed up for one year. A statistically significant difference was observed in pachymetry values during the intraoperative period (p<0.0001) and an increase of 3.05 µm (95%C1: 0.56-5.54) for each diopter was seen after epithelium removal (p0.019). We found an average Kmax difference of —2.12 D between men and women (p0.013). One year after treatment, there was a statistically significant reduction in pachymetry (p<0.0001) and Kmax (p0.0170) values. Conclusions: A significant increase in pachymetry measurements was seen during the procedure, and most patients showed a regression in Kmax and pachymetry values one year after surgery.

Crosslinking gelatin with robust inherent antibacterial natural polymer for wound healing.

Gelatin-based biomaterials are widely acknowledged as a promising choice for wound dressings, given their similarity to the extracellular matrix and biocompatibility. However, the challenge of cross-linking gelatin while preserving its biocompatibility and cost-effectiveness persists. This study aimed to enhance the properties of gelatin by incorporating the oxidized lignosulfonate (OLS) biopolymer as an inexpensive and biocompatible natural material. The polyphenolic structure of OLS acts as both a cross-linking agent and an antibacterial component. The OLS/gelatin films were prepared using a casting method with varying weight ratios (0.1, 0.2, 0.3, 0.4, and 0.5 w/w). FTIR analysis confirmed the formation of Schiff-base and hydrogen bonds between gelatin and OLS. The resulting films exhibited enhanced mechanical properties (Young's modulus ∼40 MPa), no cytotoxicity, and excellent cell adhesion and morphology. Antimicrobial tests showed significant activity against Escherichia coli and Staphylococcus aureus, with higher activity against S. aureus (17 mm inhibition zone and 99 % bactericidal rate). In vivo studies in a mouse model demonstrated that the gelatin/0.2OLS dressing significantly improved wound healing, including re-epithelialization, collagen formation, inflammation reduction, and blood vessel density, compared to untreated wounds. These findings suggest that the synthesized novel gelatin/OLS wound dressing has promising healing and antibacterial properties.

Static in-situ curing characteristics of CFRP based on near infrared laser.

STUDY ON STATIC IN-SITU CURING CHARACTERISTICS OF CFRP BASED ON NEAR INFRARED LASER: The quick curing method of carbon fibre reinforced plastics (CFRP) is one of the hotspots in current research. A static in-situ curing method for CFRP prepreg based on near-infrared laser was put forward in this study. The in-situ curing structural characteristics and the mechanism of CFRP were investigated through real-time surface temperature measurement, COMSOL temperature field simulation, 3D measurement of curing morphology and resin curing degree test. The thermal conductivity of the CFRP along the fiber direction is considerably higher than that along the perpendicular fiber direction. As a result, the temperature profile in the plane takes on an elliptical shape. During the transfer, the temperature field gradually decreases, resulting in an ellipsoidal 3D high-temperature distribution. The different shrinkage phenomena in the different curing regions between the layers lead to an irregular ellipsoidal solidification morphology of the unidirectional CFRP. The temperature in the center of the heat affected zone increases as a power exponential function with time. The area and depth of the heat-affected zone increases with the laser power, and the curing area is positively correlated with the degree of curing. As a result, curing temperature governing equations based on laser power and layer thickness have been proposed, while relationship equations based on laser power, curing depth and curing morphology have been developed. In addition, prediction equations based on curing morphology have been developed for curing degree, in order to achieve precise curing of CFRP.

The influence of radiation-induced collagen chain fragmentation, crosslinking, and sequential irradiation on the high-cycle fatigue life of human cortical bone.

Both high-cycle fatigue life and fatigue crack propagation resistance of human cortical bone allograft are radiation dose-dependent between 0 and 25 kGy such that higher doses exhibit progressively shorter lifetimes. Recently, we have shown that collagen chain fragmentation and stable crosslink accumulation may contribute to the radiation dose-dependent loss in fatigue crack propagation resistance of human cortical bone. To our knowledge, the influence of these mechanisms on high-cycle fatigue life of cortical bone have not been established. Sequential irradiation has also been shown to mitigate the loss of fatigue life of tendons, however, whether this mitigates losses in fatigue life of cortical bone has not been explored. Our objectives were to evaluate the influence of radiation-induced collagen chain fragmentation and crosslinking on the high-cycle fatigue life of cortical bone in the dose range of 0-15 kGy, and to evaluate the capability of sequential irradiation at 15 kGy to mitigate the loss of high-cycle fatigue life and radiation-induced collagen damage. High-cycle fatigue life specimens from four male donor femoral pairs were divided into 5 treatment groups (0 kGy, 5 kGy, 10 kGy, 15 kGy, and 15 kGy sequentially irradiated) and subjected to high-cycle fatigue life testing with a custom rotating-bending apparatus at a cyclic stress of 35 MPa. Following fatigue testing, collagen was isolated from fatigue specimens, and collagen chain fragmentation and crosslink accumulation were quantified using SDS-PAGE and a fluorometric assay, respectively. Both collagen chain fragmentation (p = 0.006) and non-enzymatic crosslinking (p < 0.001) influenced high-cycle fatigue life, which decreased with increasing radiation dose from 0 to 15 kGy (p = 0.016). Sequential irradiation at 15 kGy did not offer any mitigation in high-cycle fatigue life (p = 0.93), collagen chain fragmentation (p = 0.99), or non-enzymatic crosslinking (p ≥ 0.10) compared to a single radiation dose of 15 kGy. Taken together with our previous findings on the influence of collagen damage on fatigue crack propagation resistance, collagen chain fragmentation and crosslink accumulation both contribute to radiation-induced losses in notched and unnotched fatigue life of cortical bone. To maximize the functional lifetime of radiation sterilized structural cortical bone allografts, pathways other than sequential radiation should be explored to mitigate collagen matrix damage.

A conserved peptide-binding pocket in HyNaC/ASIC ion channels.

The only known peptide-gated ion channels-FaNaCs/WaNaCs and HyNaCs-belong to different clades of the DEG/ENaC family. FaNaCs are activated by the short neuropeptide FMRFamide, and HyNaCs by Hydra RFamides, which are not evolutionarily related to FMRFamide. The FMRFamide-binding site in FaNaCs was recently identified in a cleft atop the large extracellular domain. However, this cleft is not conserved in HyNaCs. Here, we combined molecular modeling and site-directed mutagenesis and identified a putative binding pocket for Hydra-RFamides in the extracellular domain of the heterotrimeric HyNaC2/3/5. This pocket localizes to only one of the three subunit interfaces, indicating that this trimeric ion channel binds a single peptide ligand. We engineered an unnatural amino acid at the putative binding pocket entrance, which allowed covalent tethering of Hydra RFamide to the channel, thereby trapping the channel in an open conformation. The identified pocket localizes to the same region as the acidic pocket of acid-sensing ion channels (ASICs), which binds peptide ligands. The pocket in HyNaCs is less acidic, and both electrostatic and hydrophobic interactions contribute to peptide binding. Collectively, our results reveal a conserved ligand-binding pocket in HyNaCs and ASICs and indicate independent evolution of peptide-binding cavities in the two subgroups of peptide-gated ion channels.

Clustered ultra-small iron oxide nanoparticles as potential T1/T2dual-modal magnetic resonance imaging contrast agents and application to tumor model.

Many studies have been conducted on the use of ultra-small iron oxide nanoparticles (USIONs) (d < 3 nm) as potential positive magnetic resonance imaging (MRI)-contrast agents (CAs); however, there is dearth of research on clustered USIONs. In this study, nearly monodispersed clustered USIONs were synthesized using a simple two-step one-pot polyol method. First, USIONs (d = 2.7 nm) were synthesized, and clustered USIONs (d = 27.9 nm) were subsequently synthesized through multiple cross-linking of USIONs with poly(acrylic acid-co-maleic acid) (PAAMA) polymers with many -COOH groups. The clustered PAAMA-USIONs exhibited very weak ferromagnetism owing to the magnetic interaction between superparamagnetic USIONs; this was evidenced by their appreciable r1= 3.9 s‒1mM‒1and high r2/r1ratio of 14.6. Their ability to function as a dual-modal T1/T2MRI-CA in T1-weighted MRI was demonstrated when they simultaneously exhibited positive and negative contrasts in T1-weighted MRI of tumor model mice after intravenous injection. They displayed positive contrasts at the kidneys, bladder, heart, and aorta and negative contrasts at the liver and tumor. .

Recent progress of poly(glycerol adipate)-based network materials toward tissue engineering applications.

Poly(glycerol adipate) (PGA) is one of the aliphatic polyesters of glycerol. The most studied biomedical application of poly(glycerol adipate) is the use of its nanoparticles as drug delivery carriers. The PGA prepolymer can be crosslinked to network materials. The biomedical application of PGA-based network materials has largely remained unexplored till recently. The PGA-based network materials, such as poly(glycerol sebacate) elastomers, can be used in soft tissue regeneration due to their mechanical properties. The modulus of elasticity of PGA elastomers is within the range of MPa, which corresponds to the mechanical properties of human soft tissues. This short review aims at briefly summarizing the possible applications of PGA-based elastomers in tissue engineering, as indicated in recent years in research publications.

Singlet oxygen-mediated photochemical cross-linking of an engineered fluorescent flavoprotein iLOV.

Genetically-encoded photoactive proteins are integral tools in modern biochemical and molecular biological research. Within this tool box, truncated variants of the phototropin 2 light-oxygen-voltage (LOV) flavoprotein have been developed to photochemically generate singlet oxygen (1O2) in vitro and in vivo, yet the effect of 1O2 on these genetically encoded photosensitizers remains underexplored. In this study, we demonstrate that the "improved" LOV (iLOV) flavoprotein is capable of photochemical 1O2 generation. Once generated, 1O2 induces protein oligomerization via covalent cross-linking. The molecular targets of protein oligomerization by cross-linking are not endogenous tryptophans or tyrosines, but rather primarily histidines. Substitution of surface-exposed histidines for serine or glycine residues effectively eliminates protein cross-linking. When used in biochemical applications, such protein-protein cross-links may interfere with native biological responses to 1O2, which can be ameliorated by substitution of the surface exposed histidines of iLOV or other 1O2-generating flavoproteins.

Pharmaceutical chitosan hydrogels: A review on its design and applications.

Chitosan (CS) has become a focal point of extensive research in the pharmaceutical industry due to its remarkable biodegradability, biocompatibility and sustainability. Chitosan hydrogels (CS HGs) are characterized by their viscoelasticity, flexibility and softness. The polar surfaces exhibit properties that mitigate interfacial tension between the hydrogel and body fluids. The inherent compatibility of CS HGs with body tissues and fluids positions them as outstanding polymers for delivering therapeutic proteins, peptides, DNA, siRNA, and vaccines. Designed to release drugs through mechanisms such as swelling-based diffusion, bioerosion, and responsiveness to stimuli, CS HGs offer a versatile platform for drug delivery. CS HGs play pivotal roles in serving purposes such as prolonging the duration of preprogrammed drug delivery, enabling stimuli-responsive smart delivery to target sites, protecting encapsulated drugs within the mesh network from adverse environments, and facilitating mucoadhesion and penetration through cell membranes. This review comprehensively outlines various novel preparation methods of CS HGs, delving into the parameters influencing drug delivery system design, providing a rationale for CS HG utilization in drug delivery, and presenting diverse applications across the pharmaceutical landscape. In synthesizing these facets, the review seeks to contribute to a nuanced understanding of the multifaceted role that CS HGs play in advancing drug delivery methodologies.

Synthesis and characterization of methacryl glycol chitosan as a novel functionally advanced thermogel for biomedical applications.

Thermo-responsive hydrogels (thermogels), known for their sol-gel transition capabilities, have garnered significant interest for biomedical applications over recent decades. However, conventional thermogels are hindered by intrinsic physicochemical and functional limitations that impede their broader utility. This study introduces methacryl glycol chitosan (MGC) as a novel thermogel, offering enhanced functionality and addressing these limitations. MGCs, synthesized through N-methacrylation of glycol chitosan, exhibit tunable thermogelling and photo-crosslinking behaviors. The thermo-reversible sol-gel transition of MGCs occurs within a 21-54 °C range, adjustable by polymer concentration and methacryl substitution degree. Photo-crosslinking using UV light further enhances the mechanical properties of MGC thermogels, creating thermo-irreversible, chemically crosslinked hydrogels. MGCs show no cytotoxic effects and effectively support cell encapsulation. In vivo studies demonstrate stable crosslinking with minimal UV-induced skin damage. Due to their unique thermo-sensitivity, multi-functionality, and customizable properties, MGC thermogels are promising novel biomaterials for various biomedical applications, particularly injectable tissue engineering and cell encapsulation, thus overcoming the limitations of conventional thermogels.

Glucose Oxidase-Immobilized Dually-Crosslinked Nanogels for Rapid-Responsive Insulin Delivery.

Despite the potential benefits of close-looped insulin delivery systems in regulating glycemic homeostasis and effectively alleviating diabetes, they still encounter challenges such as limited effectiveness in preventing low glycemic episodes due to sluggish glucose response, and issues with the instability of enzymes and carriers. In this study, dually-crosslinked and glucose oxidase (GOx)-immobilized insulin nanogels (DC-NGs@Ins) are developed for rapid-responsive and sustained hypoglycemic therapy. The DC-NGs@Ins with the phenylborate ester linker enabled the insulin release in a close-looped fashion, and moreover, immobilized GOx-generated hydrogen peroxide (H2O2) by consuming the glucose, which can further bind to phenylborate ester for enhancing glucose response and accelerating the insulin release. The dually-crosslinked structure (phenylboronic ester and UV-crosslinking) effectively minimized the initial burst release of insulin, thus preventing the potential risk of hypoglycemia. More interestingly, GOx immobilized in the nanogels mitigated GOx leakage and enhanced its multiple utilization compared to free GOx. In vivo study demonstrated that DC-NGs@Ins effectively maintained glycemic levels (BGLs) below 200 mg dL-1 for at least 8 h compared to singly-crosslinked nanogels (SC-NGs@Ins). Therefore, this intelligent insulin delivery system shows potential applications in diabetes treatment.

Chitosan-thioglycolic acid composite cross-linked with glutaraldehyde for selective recovery of Au(III) ions from e-waste leachate via reduction-coupled adsorption and incineration.

The recovery of gold (Au) from electronic waste (e-waste) has gained significant attention due to its high Au content and economic feasibility compared to natural ores. This study presents a facile, single-step approach to prepare the chitosan-thioglycolic acid composite crosslinked with glutaraldehyde (CS-TGA-GA) and demonstrates its unique capability for precious metal management, which is a less investigated application area for thiolated chitosan materials. The novel cost-effective biosorbent CS-TGA-GA demonstrated a very high adsorption capacity of 1351.9 ± 96 mg/g and selectivity for Au(III) from an acidic e-waste solution at pH 1 and 298 K. The high adsorption capacity and selectivity of the sorbent can be attributed to the abundance of -NH2, -OH, and -SH groups present on its surface. Various characterizations, such as scanning electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffractometry, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy, as well as sorption experiments, including pH, kinetic, and isotherm studies, were performed. The kinetic data align with a pseudo-second-order model and the isotherm data can be well expressed by the Freundlich model. The CS-TGA-GA composite effectively facilitated the conversion of Au(III) to Au(0), leading to the formation of Au nanoparticles that aggregated in the reaction vessel over time. Subsequently, the Au-loaded CS-TGA-GA underwent an incineration procedure, yielding recovered Au with a purity of 99.6%, as measured by X-ray fluorescence. In addition to its large uptake capacity, acid stability, and recyclability, the prepared sorbent showed a highly selective uptake of Au(III) ions in a solution containing various metal ions leached from waste printed circuit boards. These results highlight the potential of CS-TGA-GA as an adsorbent for the recovery of Au from e-waste leachate, thereby contributing to sustainable resource management.

Crosslinking modification of starch improves the structural stability of hard carbon anodes for high-capacity sodium storage.

Compared with the complex components of raw biomass, biomass derivatives with defined structures are more conducive to the controllable synthesis of hard carbon (HC) materials. Starch-based HC has garnered significant attention because of its cost-effectiveness; however, its practical applicability is limited by poor thermal stability. Herein, we propose a strategy for improving the stability of starch through self-assembly crosslinking modification, yielding high-performance HC. Starch and citric acid form a dense crosslinked structure through esterification between hydroxyl and carboxyl groups, effectively overcoming the poor thermal stability. The resulting HC exhibits a low specific surface area (SSA) and abundant closed pore structures, thereby enabling substantial sodium-ion storage. The optimized HC exhibits an improved reversible capacity of 378 mAh g-1 and an initial Coulombic efficiency (ICE) of 90.9 %. After 100 cycles at 0.5 C, it retains 98 % initial capacity. The assembled full-cell shows a high energy density of 248 Wh kg-1. Furthermore, the structure-performance relationship analysis reveals that the slope capacity is primarily affected by the defect concentration, while the plateau capacity is mainly determined by the closed pore structure. Galvanostatic intermittent titration technique (GITT) tests and in-situ Raman spectroscopy reveal that the sodium-ion storage mechanism in starch-based HC is "adsorption-intercalation/filling."

High-Performance Flexible Sensor with Sensitive Strain/Magnetic Dual-Mode Sensing Characteristics Based on Sodium Alginate and Carboxymethyl Cellulose.

Flexible sensors can measure various stimuli owing to their exceptional flexibility, stretchability, and electrical properties. However, the integration of multiple stimuli into a single sensor for measurement is challenging. To address this issue, the sensor developed in this study utilizes the natural biopolymers sodium alginate and carboxymethyl cellulose to construct a dual interpenetrating network, This results in a flexible porous sponge that exhibits a dual-modal response to strain and magnetic stimulation. The dual-mode flexible sensor achieved a maximum tensile strength of 429 kPa and elongation at break of 24.7%. It also exhibited rapid response times and reliable stability under both strain and magnetic stimuli. The porous foam sensor is intended for use as a wearable electronic device for monitoring joint movements of the body. It provides a swift and stable sensing response to mechanical stimuli arising from joint activities, such as stretching, compression, and bending. Furthermore, the sensor generates opposing response signals to strain and magnetic stimulation, enabling real-time decoupling of different stimuli. This study employed a simple and environmentally friendly manufacturing method for the dual-modal flexible sensor. Because of its remarkable performance, it has significant potential for application in smart wearable electronics and artificial electroskins.

Natural Regenerative Hydrogels for Wound Healing.

Regenerative hydrogels from natural polymers have come forth as auspicious materials for use in regenerative medicine, with interest attributed to their intrinsic biodegradability, biocompatibility, and ability to reassemble the extracellular matrix. This review covers the latest advances in regenerative hydrogels used for wound healing, focusing on their chemical composition, cross-linking mechanisms, and functional properties. Key carbohydrate polymers, including alginate, chitosan, hyaluronic acid, and polysaccharide gums, including agarose, carrageenan, and xanthan gum, are discussed in terms of their sources, chemical structures and specific properties suitable for regenerative applications. The review further explores the categorization of hydrogels based on ionic charge, response to physiological stimuli (i.e., pH, temperature) and particularized roles in wound tissue self-healing. Various methods of cross-linking used to enhance the mechanical and biological performance of these hydrogels are also examined. By highlighting recent innovations and ongoing challenges, this article intends to give a detailed understanding of natural hydrogels and their potential to revolutionize regenerative medicine and improve patient healing outcomes.

The Influence of the Structural Architecture on the Swelling Kinetics and the Network Behavior of Sodium-Alginate-Based Hydrogels Cross-Linked with Ionizing Radiation.

The present work discusses the influence of the structural architecture of sodium alginate-co-acrylic acid-poly(ethylene) oxide hydrogels, crosslinked through electron beam (e-beam) radiation processing. The most important properties of the hydrogels were studied in detail to identify a correlation between the architecture of the hydrogels and their properties. Furthermore, the effect of sodium alginate (NaAlg) concentration, the amounts of the polymer blend, and the size of the samples on hydrogel properties were investigated. The results show that the hydrogels cross-linked (0.5% and 1% NaAlg) with 12.5 kGy exhibit improved physicochemical properties. High gel fraction levels (exceeding 83.5-93.7%) were achieved. Smaller hydrogel diameter (7 mm) contributed to a maximum swelling rate and degree of 20.440%. The hydrogel network was dependent on the hydrogels' diameter and the amount of polymer blend used. The hydrogels best suited the first-order rate constants and exhibited a non-Fickian diffusion character with diffusion exponent values greater than 0.5. This study indicates that the cross-linked hydrogel has good properties, particularly because of its high degree of swelling and extensive stability (more than 180 h) in water. These findings show that hydrogels can be effectively applied to the purification of water contaminated with metals, dyes, or even pharmaceuticals, as well as materials with a gradual release of bioactive chemicals and water retention.

Identification of SLC25A46 interaction interfaces with mitochondrial membrane fusogens Opa1 and Mfn2.

Mitochondrial fusion requires the sequential merger of four bilayers to two. The outer-membrane solute carrier family 25 member (SLC25A46) interacts with both the outer and inner membrane dynamin family GTPases mitofusin 1/2 and optic atrophy 1 (Opa1). While SLC25A46 levels are known to affect mitochondrial morphology, how SLC25A46 interacts with mitofusin 1/2 and Opa1 to regulate membrane fusion is not understood. In this study, we use crosslinking mass spectrometry and AlphaFold 2 modeling to identify interfaces mediating an SLC25A46 interaction with Opa1 and Mfn2. We reveal that the bundle signaling element of Opa1 interacts with SLC25A46, and present evidence of an Mfn2 interaction involving the SLC25A46 cytosolic face. We validate these newly identified interaction interfaces and show that they play a role in mitochondrial network maintenance.

A multifunctional hydrogel dressing loaded with antibiotics for healing of infected wound.

Wound bacterial infections can significantly delay the healing process and even lead to fetal sepsis. There is a need for multifunctional dressings that possess antibacterial property, tissue adhesive property, self-healing capability, and biocompatibility to effectively treat bacteria-infected wound. In this study, we report a dual dynamically crosslinked hydrogel, OHA-PBA/PVA/Gen, which incorporates the antibiotic gentamicin (Gen) as a dynamic crosslinker. The hydrogel is formed through the formation of Schiff base bonds between phenylboronic acid-grafted oxidized hyaluronic acid (OHA-PBA) and Gen, as well as boronic acid ester bonds between OHA-PBA and polyvinyl alcohol (PVA). This unique composition imparts tissue adhesiveness, injectability and self-healing property to the hydrogel. The hydrogel also exhibits pH-responsive antibiotic release behavior due to the acid-responsive dissociation of Schiff base bonds. As a result, it demonstrates strong antibacterial activity against both Gram-positive bacteria S. aureus and Gram-negative bacteria E. coli through contact killing and diffusion killing mechanisms. Importantly, the OHA-PBA/PVA/Gen hydrogel avoids incorporation of toxic small molecular crosslinking agents, and all the components of the hydrogel are biocompatible, ensuring its biosafety. In a S. aureus-infected wound mouse model, this hydrogel effectively eradicated bacteria and promoted angiogenesis, leading to significantly accelerated wound healing. These results highlight the potential of the dual dynamically crosslinking hydrogel OHA-PBA/PVA/Gen as a multifunctional wound dressing for the treatment of bacteria-infected wound.

Under Water Superelastic Porous Nanofibrous Sponge for Efficient RNA Separation and Purification.

Developing monolithic materials for chromatography columns with a novel interconnected porous structure is vital for the enhancement of the separation efficiency of RNA purification processes. Herein, a porous nanofibrous sponge (PNFS) is constructed by freeze molding and freeze-drying a nanofiber dispersion with ethylene vinyl alcohol copolymer nanofibers as the skeleton, chitosan (CS) and polyethylenimine (PEI) as the binders, and glutaraldehyde (GA) as the crosslinking agent. The results show that when the CS content of the dispersion is 1.5 wt %, PNFS demonstrates a high static adsorption capacity of 406.5 mg/g (30.7 mg/m2) and a dynamic adsorption capacity of 382.6 mg/g (28.9 mg/m2) at a flow rate of 1 mm/min. Moreover, PNFS shows a high specific adsorption performance toward RNA in the presence of bovine serum albumin, lecithin, or DNA by adjusting the solution pH value and the method of gradient elution. Besides, PNFS presents exceptional performance in the rapid separation of RNA from HT22 cells without degradation. This result can be attributed to optimized morphology, pore structure, and comprehensive performance of PNFS, benefiting from the synergistic effect of the highly oriented porous structure and CS-PEI interaction derived from the high-density adsorption ligands on the channel walls of PNFS. This work provided an efficient strategy to handle the permeability/adsorptivity trade-off for ion-exchange chromatographic materials.