Porous Poly Research Articles

Fine‐Tuning of Hydrophilic Properties of Asymmetrically Porous Poly(ε‐Caprolactone)‐Based Nanofibrous Scaffolds Containing Dexamethasone for Bone Tissue Engineering Applications

Fine‐Tuning of Hydrophilic Properties of Asymmetrically Porous Poly(ε‐Caprolactone)‐Based Nanofibrous Scaffolds Containing Dexamethasone for Bone Tissue Engineering Applications

Navigating the Semiochemical Landscape: Attraction of Subcortical Beetle Communities to Bark Beetle Pheromones, Fungal and Host Tree Volatiles.

Subcortical beetle communities interact with a wide range of semiochemicals released from different sources, including trees, fungi, and bark beetle pheromones. While the attraction of bark beetles, their insect predators, and competitors to bark beetle pheromones is commonly studied, the attraction of these beetle communities to other sources of semiochemicals remains poorly understood. We tested the attraction of bark and wood-boring beetles and their predators to host stress volatiles, fungal volatiles, and a mountain pine beetle lure in the field. Host stress volatiles were derived from lodgepole pine trees stressed by three fungal symbionts of mountain pine beetle and two common phytopathogens. Our results showed that bark beetles, particularly mountain pine beetles, show a preference for a combination of fungal volatiles, particularly 2-methyl-1-butanol and its lures. Without the addition of lures, 2-methyl-1-butanol was also identified as a key fungal volatile in the attraction of mountain pine beetle competitors from the Cerambycidae and Buprestidae families. Predators in the Elateridae and Staphylinidae families showed attraction to host stress volatiles and the healthy tree volatile profiles. These findings suggest that these semiochemicals warrant further field testing for potential use in monitoring and management of subcortical beetle populations.

Nuclear and Mitochondrial Genome Assemblies for the Endangered Wood-Decaying Fungus Somion occarium.

Somion occarium is a wood-decaying bracket fungus belonging to an order known to be rich in useful chemical compounds. Despite its widespread distribution, S. occarium has been assessed as endangered on at least 1 national Red List, presumably due to loss of old-growth forest habitat. Here, we present a near-complete, annotated nuclear genome assembly for S. occarium consisting of 31 Mbp arranged in 11 pseudochromosomes-9 of which are telomere-to-telomere-as well as a complete mitochondrial genome assembly of 112.9 Kbp. We additionally performed phylogenomic analysis and annotated carbohydrate-active enzymes (CAZymes) to compare gene and CAZyme content across closely related species. This genome was sequenced as the representative for Kingdom Fungi in the European Reference Genome Atlas Pilot Project.

Synthesis of Three-Dimensional Porous Porphyrin Poly(ionic liquid)s via the Menshutkin Reaction: Designing Metal-Free and Metal-Based Catalysts for Efficient Conversion of CO2 into Cyclic Carbonates

Synthesis of Three-Dimensional Porous Porphyrin Poly(ionic liquid)s via the Menshutkin Reaction: Designing Metal-Free and Metal-Based Catalysts for Efficient Conversion of CO₂ into Cyclic Carbonates

The effect of PEO/NaCl dual porogens in the fabrication of porous PCL membranes via a solid-state blending approach

In this investigation, the influence of a combination of poly(ethylene-oxide) (PEO) and salt (NaCl) as water-soluble porogens on the synthesis of sustainable porous poly(ε-caprolactone) (PCL) membranes is explored. Nine mixture compositions are examined. PCL sheets are fabricated through the cryomilling, hot pressing, and porogen leaching approach. The resulting sheets are investigated for their morphologies, porosities, water uptake, and mechanical properties. Thick sheets display a porous lamellar structure with porosities ranging from 47.4% to 70.8%. Lamellae exhibit various surface features ranging from smooth surfaces, rough with pinholes, globular, fibrillar, and finally skeletal structures. Higher salt contents result in more compact lamellae with higher interconnected porosities on the lamellae surfaces. Samples demonstrate significant water uptake, increasing with higher porosities, while mechanical properties decrease. Regression analysis is used to fit the mechanical properties of the thin sheets, revealing second order polynomial functions of porosity. Additionally, the sandwich method is successfully employed to create porous membrane surfaces, yielding various distinct morphologies, including a notable feather-like layered structure and a hierarchal particulate structure with large particles coated with aggregates of tiny particles. These findings contribute to understanding the synthesis and properties of sustainable porous polymer membranes, with implications for various applications.

Functionalized Microsphere Platform Combining Nutrient Restriction and Combination Therapy to Combat Bacterial Infections.

The escalating prevalence of multidrug-resistant (MDR) bacterial infections has emerged as a critical global health crisis, undermining the efficacy of conventional antibiotic therapies. This pressing challenge necessitates the development of innovative strategies to combat MDR pathogens. Advances in multifunctional drug delivery systems offer promising solutions to reduce or eradicate MDR bacteria. Inspired by the fact that the growth of bacteria requires essential nutrients, core-shell porous poly(lactic-co-glycolic acid) (PLGA) microspheres coated with pH-responsive polydopamine (PDA) were fabricated to improve delivery, resulting in enhanced efficacy through nutrient restriction and combination therapy. The PDA chelates iron ions in the environment, preventing bacteria from absorbing iron and thus suppressing their growth and proliferation. Subsequently, the released antibiotics from the porous PLGA core, rifampicin and polymyxin B, accelerate bacterial eradication by disrupting their inner and outer membrane structures. Such a multifunctional microsphere platform clears 99% Salmonella Typhimurium in 4 h and shows increased efficiency in a lethal intestinal infection model in mice. These findings provide a drug delivery system that integrates bacterial nutrient restriction and antibiotic killing, highlighting the potential of targeting bacterial iron regulation as a strategy for developing new antimicrobial delivery systems to address MDR bacterial infections.

Biological and molecular characterization of nectrial species associated with an avocado decline syndrome

Background/Objective. Nectriaceae members increased regional occurrence in Michoacán since 2019. However, root species identity, geographic distribution, and association to other families are unknown. The objective was to characterize biological and molecularly species of Nectria associated with Persea americana. Materials and Methods. Seventy samples of wilt trees from 13 municipalities in Michoacán were processed. Thirty isolates selected based on epidemiological criteria were cultured in malt-agar, PDA, and oat-agar extracts to determine cultural and morphological characterization. Five morphotypes of Nectria with varying radial growth and brown coloration were obtained. From mycelial DNA, TEF 1- and RPB2 genes were amplified, sequences were cleaned and aligned with SeqAssem and MAFFT, respectively. Bayesian inference and maximum parsimony phylogenetic algorithms were performed using PAUP 4.0 and MrBayes 3.2 complemented with 66 and 65 sequences from GenBank for TEF 1 and RPB2, respectively. S. chartarum was used as the external species and four other Hypocreales. Results. Bayesian inference revealed greater phylogenetic consistency. Three genera and three species were identified with TEF 1- (>94 % homology) and three genera and five species with RPB2 (>97 % homology) belonging to Ilyonectria (56 %), Dactylonectria (33 %), Mariannaea (6 %), and Thelonectria (3 %). Associations of Nectria were observed mainly to Armillaria (97.1 %), Fusarium (92.9 %), Paecilomyces (56.4 %), and Morthierella (47.3 %). Conclusion. A decline syndrome in avocado trees associated with a fungal complex characterized by descending defoliation, wilt, reduced fruit size, and root necrosis is postulated. This is the first report of Nectria associated fungi in avocado trees in Mexico.

Electron-deficient two-dimensional poly(arylene vinylene) covalent organic frameworks: efficient synthesis and host-guest interaction.

Crystalline and porous 2D poly(arylene vinylene)s (2D PAVs), i.e. vinylene-linked 2D conjugated covalent organic frameworks, represent promising materials for electronic and electrochemical applications. Chemically robust 2D PAVs with strong electron affinity are highly desirable for effective host-guest charge transfer to achieve enhanced device performance. Herein, we report the efficient synthesis and host-guest interaction of two novel 2D PAVs incorporating electron-deficient bipyrazine units with a N-free 2D PAV as a reference. They are crystalline and chemically robust. Various spectroscopies coupled with theoretical calculations indicate that the abundant N sites boost the electron affinity of 2D PAVs. We test their efficiency in hosting guest sulfur species and find that the electron-deficient materials help to physically confine and stabilize sulfur/polysulfide (e.g., Li2S6) molecules with facilitated intermolecular charge transfer in the porous channels. As a result, using sulfur encapsulated by 2D PAVs as electrode materials, we achieve high specific capacities with excellent capacity retention after 200 charge-discharge cycles for Li-sulfur batteries.

Probe-infused polymer monolithic sensor for colorimetric detection of Pb2+ in environmental water samples and tobacco extracts.

This study focuses on developing an affordable and cost-effective colorimetric solid-state optical sensor for target-specific naked-eye detection of Pb2+, offering significant potential for real-time environmental monitoring and public health applications. The indigenously developed porous polymer monolithic template, poly(lauryl methacrylate-co-ethylene glycol dimethacrylate) (poly(LMC-co-EGDMA) is infused with a chromoionophoric probe, i.e., 6,6-(naphthalene-1,5-diyl bis(diazene-2,1-diyl)bis(4-(butan-2-yl)phenol) (NDBP) to develop a durable/reusable solid sensor. The perforated structural assemblies of the porous poly(LMC-co-EGDMA) are analyzed using a range of microscopic, spectroscopic, and diffraction methods. The template features a homogeneous configuration of interlinked macro/mesoporous networks, allowing for the enhanced integration of NDBP probe molecules to facilitate rapid and improved Pb2+ detection. The fabricated sensor demonstrates a significant solid-state colorimetric shift from pale peach to deep maroon in proportion to Pb2+ concentration, with a precise absorption peak at 543 nm. The operational parameters of the poly(LMC-co-EGDMA)NDBP sensor are optimized to maximize the ion-sensing ability. The sensor demonstrates a linear signal response from 0 to 300 ppb for Pb2+ and corresponding detection and quantification limits of 0.28 and 0.93 ppb, respectively. The sensing effectiveness of the sensor using cigarette samples and natural water samples reveals outstanding accuracy with recovery results of ≥ 98.9 % (RSD ≤1.8 %) and ≥ 99.1 %, with RSD of ≤ 1.7 % from quadruplicate analysis. The proposed solid-state sensor offers exceptional sensitivity and selectivity for trace Pb²⁺ detection with a rapid response time of 40 s. The cost-effective and portable sensor provides a valuable tool for environmental monitoring and public health protection by enabling fast, on-site detection of the toxic Pb2+ in contaminated water and tobacco samples, particularly for developing and underdeveloped regions with limited access to sophisticated instruments. Its reusability and accuracy features offer a sustainable and practical solution for addressing widespread lead pollution, thus contributing to safer water quality assessments and pollution control.

Antibacterial porous Poly(Tannin-Urethane) network buoys achieve selective uranium reduction and extraction from seawater

Antibacterial porous Poly(Tannin-Urethane) network buoys achieve selective uranium reduction and extraction from seawater

Porous Nanocomposite Implants With Gold Nanoparticles for Plastic Surgery

ABSTRACTThis study presents an innovative approach to improve implant biointegration and reduce implant‐associated infections using porous poly(vinyl formal) nanocomposite matrices incorporated with gold nanoparticles and antimicrobial/anticancer drugs for plastic surgery applications. The porous matrices were characterized using physicochemical techniques and in vitro biochemical assays. The results demonstrated the biocompatibility of PVF nanocomposites and their potential for functionalization with various bioactive molecules and drugs, thereby enhancing their therapeutic efficacy. In vivo studies in rabbits revealed progressive replacement of implants with fibrous tissue, indicating successful biointegration with the surrounding soft tissues. Future research will focus on the long‐term biocompatibility and functionalization of these nanocomposite implants for plastic surgery and explore their potential in other biomedical applications such as wound healing, tissue engineering, and scaffolds for cell growth and differentiation.

Фаутность еловых древостоев северо-таежного района Архангельской области

The results of studying the defectiveness of spruce forests in the northern taiga zone of the Arkhangelsk Region are presented. Defectiveness has a significant impact on the sanitary condition, marketability and sustainability of forest plantations. The study has been conducted from 2020 to 2023 using materials obtained from sample plots laid in mature spruce plantations, modal in terms of basic taxation parameters. Before starting the field work, the cartographic databases have been studied. The sample size has been determined by the variability of the taxational diameter of the main species and the experiment accuracy. In each test area, all trees have been enumerated by species, diameter at a height of 1.3 m and by condition categories. For each tree, the presence of defects affecting marketability and fruit bodies of wood-destroying fungi has been noted. To determine the age of the trees in the sample plot, core samples have been taken from the root collar. To study the patterns of the defectiveness spread and obtain mass material, statistical survey sites have been laid on fresh cuttings. When rot has been detected on the stump, the diameter of the rot has been measured and its type and stage have been determined. The age of the trees has been determined by the annual rings on the stumps. In the presence of rot, age has been determined by correlation with the diameter of the stump. The trees have then been grouped by their respective age classes. In the course of the research, defectiveness indicators have been studied and analyzed in various forest growth conditions. It has been revealed that with an increase in the age class, the occurrence of all defects increases. The most obvious dependence has been recorded for rots. The amount of rots varies from 5.1 to 29.0 %, depending on the type of forest growth conditions. The proportion of rots decreases with the deterioration of forest conditions. The most common wood-destroying fungus is the root sponge (Heterobasidion annosum (Fr.) Bref.). There is an increase in the incidence of wood-destroying fungi in trees with increasing diameter. The average stage of butt rot has been 2.8. The study of the defectiveness will improve the accuracy of assessing the resource potential of coniferous plantations in the Arkhangelsk Region.

Effect of stretching ratio on the structure and enactment of porous PVDF-HFP hollow fiber membranes for CO2 absorption

Carbon dioxide (CO2) is responsible for increment of the Earth surface temperature and the subsequent environmental issues. In this regard, membrane contactor is one of the emerging technologies that can be applied for controlling CO2 emission. More specifically, the intrinsic structure of membrane plays an important role to govern the performance of CO2 absorption. In this study, considering stretching ratio (SR) as a key factor to affect membrane structural properties, highly porous poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) hollow fiber membranes were fabricated by a non-solvent induced phase separation method. The results showed that the membrane dimension and thickness were significantly reduced by optimizing the SR. The optimum membrane structure was found at SR of 1.5 where the mean pore size, CO2 permeance, collapsing pressure and liquid entry pressure of 0.032 μm, 3440 GPU, 550 kPa and 500 kPa were achieved, respectively. The prepared membranes showed open structure with overall porosity of more than 80%. The upgraded membrane at SR of 1.5 presented the maximum CO2 absorption flux of 9.8 × 10− 4 mol/m2 s and the minimum mass transfer resistance of 49,544 (m/s)−1. Furthermore, a stable CO2 absorption performance was achieved during 80 h continuous operation with a flux decline of only about 9%. The findings of this work demonstrated that by applying a cost-effective fabrication method, we can potentially enhance the PVDF-HFP membrane properties for CO2 adsorption without requiring an additional post-modification step.

Behavior of PGS/apatite foam scaffolds during incubation in SBF, PBS, Ringer's solution, artificial saliva, and distilled water.

Poly(glycerol sebacate) is a polymeric material with potential biomedical application in the field of tissue engineering. In order to act as a biodegradable scaffold, its incubation study is vital to simulate its behavior. This study explores the degradation of porous poly(glycerol sebacate)/hydroxyapatite scaffolds subjected to incubation in various physiological solutions. The research involved monitoring pH and conductivity values over a 14-day period, as well as analyzing the swelling capacity and mass alterations of the scaffolds. In simulated body fluid (SBF) and phosphate-buffered saline (PBS), the pH levels remained relatively stable, whereas Ringer's solution caused a pH decrease. Conversely, artificial saliva demonstrated an increase in pH, and distilled water caused a slight decrease. The conductivity values remained stable in SBF and Ringer's solution, slightly decreased in PBS, increased in artificial saliva, and significantly increased in distilled water. The swelling capacity of the scaffolds varied depending on the solution used, with the lowest equilibrium swelling observed in SBF and PBS. The effect of the presence of ceramics on this parameter was also observed. The mass changes of the scaffolds indicated deposition of particles or salts from the incubation solutions, and subsequent rinsing in distilled water led to a decrease in mass. Scanning electron microscopy (SEM) imaging and elemental analysis confirmed the presence of crystallized salts on the scaffold surfaces after incubation in SBF. Surface roughness measurements revealed changes in roughness depending on the solution, with deposition of additional layers in SBF and degradation in artificial saliva. In summary, the scaffolds exhibited biodegradation in physiological solutions, with variations in pH, conductivity, swelling capacity, mass changes, and surface morphology depending on the specific solution and scaffold composition.

Four species of Ciidae (Coleoptera: Tenebrionoidea) from Jeju-island in Korea associated with the Bracket Fungus, Inonotus mikadoi (Basidiomycetes: Hymenochaetaceae)

Four species of Ciidae (Coleoptera: Tenebrionoidea) from Jeju-island in Korea associated with the Bracket Fungus, Inonotus mikadoi (Basidiomycetes: Hymenochaetaceae)

Highly durable superhydrophobic bilayer nanofibrous composite membrane with intermediate interlocked network inspired by mortise and tenon connections for membrane distillation

Highly durable superhydrophobic bilayer nanofibrous composite membrane with intermediate interlocked network inspired by mortise and tenon connections for membrane distillation

Bioactive Coatings on 3D Printed Polycaprolactone Scaffolds for Bone Regeneration: A Novel Murine Femur Defect Model for Examination of the Biomaterial Capacity for Repair

AbstractBone tissue engineering seeks to develop treatment approaches for nonhealing and large bone defects. An ideal biodegradable scaffold will induce and support bone formation. The current study examines bone augmentation in critical‐sized bone defects, using functionalized scaffolds, with the hypothesized potential to induce skeletal cell differentiation. 3D printed, porous poly(caprolactone) trimethacrylate (PCL‐TMA900) scaffolds are applied within a murine femur defect, stabilized by a polyimide intramedullary (IM) pin. The PCL‐TMA900 scaffolds are coated with i) elastin‐like polypeptide (ELP), ii) poly(ethyl acrylate) (PEA)/fibronectin (FN)/bone morphogenetic protein‐2 (PEA/FN/BMP‐2), iii) both ELP and PEA/FN/BMP‐2, or iv) Laponite nanoclay binding BMP‐2. Sequential microcomputed tomography (µCT) and histological analysis are performed. PCL‐TMA900 is robust and biocompatible and when coated with the nanoclay material Laponite and BMP‐2 induce consistent, significant bone formation compared to the uncoated PCL‐TMA900 scaffold. Critically, the BMP‐2 is retained, due to the Laponite, producing bone around the scaffold in the desired shape and volume, compared to bone formation observed with the positive control (collagen sponge/BMP‐2). The ELP and/or PEA/FN/BMP‐2 scaffolds do not demonstrate significant or consistent bone formation. In summary, Laponite/BMP‐2 coated PCL‐TMA900 scaffolds offer a biodegradable, osteogenic construct for bone augmentation with potential for development into a large scale polymer scaffold for clinical translation.

Formation of bio-based cyclic carbonates from CO2 and renewable feedstocks via porous poly(azomethine) -based heterogeneous catalysts approach

Formation of bio-based cyclic carbonates from CO2 and renewable feedstocks via porous poly(azomethine) -based heterogeneous catalysts approach

Pore-forming aegerolysin and MACPF proteins in extremotolerant or extremophilic fungi.

Aegerolysin proteins are involved in various interactions by recognising a molecular receptor in the target organism. The formation of pores in combination with larger, non-aegerolysin-like protein partners (such as membrane attack complex/perforin proteins [MACPFs]) is one of the possible responses in the presumed competitive exclusion of other organisms from the ecological niche. Bicomponent pairs are already observed at the gene level. Fungi growing under extreme conditions can be divided into ubiquitous and extremotolerant generalists which can compete with mesophilic species and rare, isolated extremophilic and extremotolerant specialists with narrow ecological amplitude that cannot compete. Under extreme conditions, there are fewer competitors, so fungal specialists generally produce less diverse and complicated profiles of specialised molecules. Since extremotolerant and extremophilic fungi have evolved in numerous branches of the fungal tree of life and aegerolysins are unevenly distributed across fungal genomes, we investigated whether aegerolysins, together with their partner proteins, contribute to the extreme survival ecology of generalists and specialists. We compiled a list of 109 thermo-, psihro-, acido-, alkali-, halo-, metallo- and polyextremo-tolerant/-philic fungal species. Several challenges were identified that affected the outcome: renaming fungal species, defining extremotolerant/extremophilic traits, identifying extremotolerant/extremophilic traits as metadata in databases and linking fungal isolates to fungal genomes. The yield of genomes coding aegerolysins or MACPFs appears to be lower in extremotolerant/extremophilic fungi compared to all fungal genomes. No candidates for pore-forming gene pairs were identified in the genomes of extremophilic fungi. Aegerolysin and MACPFs partner pairs were identified in only two of 69 species with sequenced genomes, namely in the ubiquitous metallotolerant generalists Aspergillus niger and A. foetidus. These results support the hypothesised role of these pore-forming proteins in competitive exclusion.

Gel polymer electrolytes containing SiO2 spheres with tuned sizes to increase rechargeability of quasi-solid-state Zn-air batteries

Gel polymer electrolytes containing SiO2 spheres with tuned sizes to increase rechargeability of quasi-solid-state Zn-air batteries