Search Results (807)

Membrane distillation demonstrates ideal separation performance towards saline water; however, it fails to accomplish the classification and recovery of multiple components from complex saline solutions (i.e., heavy metal ion-laden saline water in process industries). Herein, an adsorption–membrane distillation (MD) coupling process was proposed, as an example of a Pb(II)/NaCl mixed solution, in which the prepared adsorption membrane was firstly employed to adsorb heavy metal ions in the mixed solution and then the brine was concentrated by the MD process to realize water source recovery and utilization. Firstly, an FeOOH@PVDF adsorptive membrane was fabricated to adsorb Pb(II) ions. It was demonstrated that chemical adsorption was identified as the dominant mechanism, and the composite membrane showed excellent selective adsorption for Pb(II). Following this, the omniphobic membrane was then employed to concentrate the Pb(II)-removed saline solution, maintaining a water flux of 16.12 kg·m⁻²·h⁻¹ at a concentration factor of 7.7, demonstrating excellent MD concentration performance. Through this coupled process, the saline wastewater containing heavy metal ions was successfully separated into purified water and concentrated brine without heavy metal ions, providing a novel approach for the treatment and recycling of complex saline wastewater. Full article

Determining the active substance content in the tested product is an essential part of research for overall assessment of the quality of a medicinal substance. This role can be successfully performed by membrane electrodes that are selective for a specific drug. The novelty of the presented research is the development of the first ion-selective electrode with a polymer membrane phase with the octenidine (OCT) function. Classical ion-selective electrodes (ISE), polymer electrodes with an internal Ag/AgCl electrode, and electrode bodies with glassy carbon were used for the research. The membranes were prepared based on cation exchangers from the borate group and neutral cyclodextrin. All sensors have good parameters, e.g., the polymer electrode with KtpClPB is characterised by a wide linear range of −logc 6−3, a low limit of detection 5 × 10⁻⁷ M, and a near-Nernstian, reproducible slope of characteristics of 31.41 ± 1.14 mV/decade. It can be seen that a stable, reversible potential and a short response time were achieved for this sensor. The obtained favourable selectivity coefficients of the electrode determined in relation to excipients allowed direct determination of octenidine, e.g., in lozenges. The results obtained with the calibration curve method show a recovery of 97% and a precision of SD 2.3 mg/L, which indicates that the data are consistent with the pharmacopoeia requirements. Full article

The efficient purification of Pb(II)-containing wastewater is essential for safeguarding public health and maintaining the aquatic environment. In this study, novel hydrous ferric oxide (HFO) nanoparticle-embedded poly(vinylidene fluoride) (PVDF) composite adsorption membranes were developed through a simple blending method for efficient Pb(II) removal. This composite membrane (denoted as HFO-PVDF) combines the excellent selectivity of HFO nanoparticles for Pb(II) with the membrane’s advantage of easy scalability. The optimized HFO-PVDF_(1.5) membrane achieved adsorption equilibrium within 20 h and exhibited excellent adsorption capacity. Moreover, adsorption capacity markedly enhanced with increasing temperature, confirming the endothermic nature of the process. The developed HFO-PVDF membranes demonstrate significant potential for real-world wastewater treatment applications, exhibiting exceptional selectivity for Pb(II) in complex ionic matrices and could be effectively regenerated via a relatively straightforward process. Furthermore, filtration and dynamic regeneration tests demonstrated that at an initial Pb(II) concentration of 5 mg/L, the membrane operated continuously for 10–13 h before regeneration, treating up to 200 L/m² of wastewater before breakthrough, highlighting potential for cost-effective industrial wastewater treatment. This study not only demonstrates the high efficiency of the HFO-PVDF membrane for heavy metal ion removal but also provides a theoretical foundation and technical support for its practical application in water treatment. Full article

The TMEM16 (Anoctamin) family comprises a group of transmembrane proteins involved in diverse physiological processes, including ion transport and phospholipid scrambling. TMEM16F (Anoctamin 6), a phospholipid scramblase and nonselective ion channel, plays a central role in membrane remodeling, blood coagulation, immune responses, and cell death pathways through its ability to externalize phosphatidylserine in response to elevated intracellular calcium levels. Consequently, modulating TMEM16F activity has emerged as a promising strategy for the development of new therapeutic applications. Despite the functional importance of TMEM16F, TMEM16F modulators have received little study. In a previous study, we generated TMEM16F-specific affibodies by biopanning a phage display library for affibodies that bind to brain-specific TMEM16F (hTMEM16F) variant 1. In this study, we selected six other affibodies from among the 38 previously sequenced affibody candidates and characterized them. After purification, we confirmed that two of these affibodies bound to human TMEM16F with high affinity. To provide functional insights into how these affibodies modulate TMEM16F activity, we tested whether they could exert functional effects at the cellular level. Finally, we show that TMEM16F affibody attenuated the neuronal cell death induced by glutamate and microglial phagocytosis, suggesting that these affibodies might have potential therapeutic and diagnostic applications. Full article

Proton-exchange membranes (PEMs) are the pivotal components of vanadium redox flow batteries (VRFBs) and play a critical role in the comprehensive output performance of VRFB systems. Currently, the most widely commercialized membranes are Nafion series membranes produced by DuPont, Wilmington, DE, USA, but the high vanadium permeability and cost hinder their large-scale promotion. Hence, there is an active demand for developing a low-cost, high-performance, and energy-efficient PEM to promote the commercialization of VRFB systems. In this paper, sulfonated poly(ether ether ketone) (SPEEK) as matrix and zirconia nanoparticles as inorganic filler were used for composite modification to prepare a series of SPEEK–ZrO₂ organic–inorganic hybrid membranes for VRFBs. The thickness of these membranes was 50–100 μm. Compared with Nafion 115 (thickness 128 μm), composite membranes demonstrated obvious cost advantages. The results showed that the SP–Z-X series membranes had higher water uptake (53.26–71.1%) and proton conductivity (0.11–0.24 S cm⁻¹). SP–Z-5 displayed the best comprehensive output performance at 200 mA cm⁻² (CE: 99.01%, VE: 81.95%, EE: 81.11%). These hybrid membranes are very cost-effective and exhibit high potential for application in VRFB applications, and are expected to lead to the industrial application of VRFBs on a large scale. Full article

Apigenin (AP) is a natural flavonoid with senomorphic potential and neuroprotective action; however, poor aqueous solubility (<1 μg/mL) limits its bioavailability and therapeutic use. Therefore, the aim of this study was to obtain an amorphous dispersion of AP and evaluate its biological properties. Screening of AP solubilization capabilities under supercritical carbon dioxide processing conditions showed that the system with Soluplus (SOL) achieved the greatest improvement in AP dissolution (6455.4 ± 27.2 μg/mL). Using optimized process parameters (50 °C, 6500 PSI), the AP solubility increased to 8050.2 ± 35.1 μg/mL. X-ray powder diffraction (XRPD) confirmed amorphization, aligning with improved dissolution of AP in both acidic and neutral pH media. As a result, using the PAMPA model, an improvement in AP penetration through membranes simulating gastrointestinal and blood–brain barriers was demonstrated. The significant stability of the obtained amorphous AP dispersion (12 months at room conditions) was associated with stabilizing AP–solubilizer intermolecular interactions, mainly expressed as the shifts in the bands of AP in the range of 1018–1269 cm⁻¹ observed in ATR-FT-IR spectra. Chromatographic analysis confirmed the lack of AP decomposition immediately after the preparation of the amorphous dispersion, as well as after 12 months. As expected, the improvement of AP solubility is correlated with better biological activity assessed in selected in vitro tests such as antioxidant properties (2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and cupric ion reducing antioxidant capacity (CUPRAC) assays) and anticholinesterase inhibition capabilities (AChE and BChE assays). The effect of the studies on improving AP solubility under supercritical carbon dioxide processing conditions is obtaining a stable amorphous AP dispersion (up to 12 months). Regardless of the pH of the media, an improvement in AP dissolution and penetration, conditioned by the passive diffusion process, through biological membranes was noted. Moreover, a more efficient antioxidant and neuroprotective effect of AP in the developed amorphous dispersion can also be suggested. Full article

The consistent quality control of ultrapure water (UPW) in semiconductor manufacturing depends on removing trace organonitrogen compounds such as urea. Due to its high solubility, chemical stability, and neutral polarity, urea is inadequately removed by conventional processes. Even at low concentrations, it elevates total organic carbon (TOC) and reduces electrical resistivity. The use of reclaimed water as a sustainable feed stream amplifies this challenge because its nitrogen content is variable and persistent. Conventional methods such as reverse osmosis, ultraviolet oxidation, and ion exchange remain limited in treating urea due to its uncharged, low-molecular-weight nature. This review examines the performance and limitations of these processes and explores electrochemical oxidation (EO) as an alternative. Advances in EO are analyzed with attention to degradation pathways, electrode design, reaction selectivity, and operational parameters. Integrated systems combining EO with membrane filtration, adsorption, or chemical oxidation are also reviewed. Although EO shows promise for selectively degrading urea, its application in UPW production is still in its early stages. Challenges such as low conductivity, byproduct formation, and energy efficiency must be addressed. The paper first discusses urea in reclaimed water and associated removal challenges, then examines both conventional and emerging treatment technologies. Subsequent sections delve into the mechanisms and optimization of EO, including electrode materials and operational parameters. The review concludes with a summary of main findings and a discussion of future research directions, aiming to provide a comprehensive foundation for validating EO as a viable technology for producing UPW from reclaimed water. Full article

Polymer inclusion membranes (PIMs) have undergone substantial advancements in their selectivity and efficiency, driven by their increasing deployment in separation processes, environmental remediation, and sensing applications. This review presents recent progress in the development of PIMs, focusing on strategies to enhance ion and molecule selectivity through the incorporation of novel carriers, including ionic liquids and task-specific extractants, as well as through polymer functionalization techniques. Improvements in mechanical and chemical stability, achieved via the utilization of high-performance polymers such as polyvinylidene fluoride (PVDF) and polyether ether ketone (PEEK), as well as cross-linking approaches, are critically analyzed. The expanded application of PIMs in the removal of heavy metals, organic micropollutants, and gas separation, particularly for carbon dioxide capture, is discussed with an emphasis on efficiency and operational robustness. The integration of PIMs with electrochemical and optical transduction platforms for sensor development is also reviewed, highlighting enhancements in sensitivity, selectivity, and response time. Furthermore, emerging trends towards the fabrication of sustainable PIMs using biodegradable polymers and green solvents are evaluated. Advances in scalable manufacturing techniques, including phase inversion and electrospinning, are addressed, outlining pathways for the industrial translation of PIM technologies. The review concludes by identifying current limitations and proposing future research directions necessary to fully exploit the potential of PIMs in industrial and environmental sectors. Full article

Amid concurrent pressures on water and material resources, recovering valuable ions like lithium and nutrients from brines and wastewater is a critical tenet of the circular economy. This review provides a critical assessment of electro-driven membranes (EDMs) as a key technology platform for achieving this goal with high energy efficiency. A comprehensive synthesis and analysis of the current state-of-the-art of core EDM technologies, including electrodialysis (ED) and membrane capacitive deionization (MCDI), is presented, focusing the analysis on the performance metrics of specific energy consumption and ion selectivity. The findings reveal that the optimal EDM technology is highly application-dependent, with MCDI excelling for dilute streams and ED for concentrated ones. While significant advances in monovalent selective membranes have enabled lithium recovery, achieving high selectivity between ions of the same valence (e.g., Li⁺/Na⁺) remains a fundamental challenge. Moreover, persistent issues of membrane fouling and scaling continue to inflate energy consumption and represent a major bottleneck for industrial-scale deployment. While EDMs are a vital technology for ion resource recovery, unlocking their full potential requires a dual-pronged approach: advancing materials science to design novel, highly selective membranes, while simultaneously developing intelligently integrated systems to surmount existing performance and economic barriers. Full article

Chlorpyrifos (CPF), an organophosphate pesticide, is known to induce pulmonary toxicity through oxidative stress, mitochondrial dysfunction, and inflammation. Astaxanthin (ASX), a xanthophyll carotenoid derived primarily from marine microalgae (Haematococcus pluvialis), possesses strong antioxidant properties and has demonstrated cellular protective effects in numerous oxidative stress studies. However, its efficacy against CPF-induced lung cell damage remains uncharacterized. This study revealed the protective role of ASX, as a pretreatment and co-treatment, against CPF-induced cytotoxicity in human A549 lung adenocarcinoma cells by assessing cell viability, intracellular reactive oxygen species (IROS), total oxidative status (TOS), total antioxidant capacity (TAC), mitochondrial membrane potential (MMP), intracellular calcium ions (Ca²⁺), lactate dehydrogenase (LDH) release, malondialdehyde (MDA) levels, glutathione peroxidase (GPx) activity, superoxide dismutase (SOD) activity, DNA fragmentation, and apoptosis/inflammation-associated gene expression. CPF treatment significantly decreased cell viability and TAC, while elevating IROS, TOS, MMP, intracellular Ca²⁺, and LDH release. CPF also increased MDA levels and suppressed GPx and SOD activities. DNA fragmentation and quantitative polymerase chain reaction (qPCR) analysis revealed upregulation of pro-apoptotic and inflammatory markers such as BCL2-associated X protein (BAX), caspase-3 (CASP3), tumor protein p53 (TP53), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), nuclear factor kappa B (NFκB), and voltage-dependent anion-selective channel protein 1 (VDAC1) and suppression of anti-apoptotic B-cell lymphoma 2 (BCL2) and antioxidant defense genes nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1). ASX treatment, particularly when administered as a pretreatment, significantly reversed CPF-induced oxidative and inflammatory responses by restoring SOD, GPx, and TAC levels, reducing IROS, TOS, MDA, and LDH release, and downregulating apoptotic and inflammatory gene expressions. ASX pretreatment notably decreased MMP and intracellular Ca²⁺ levels, indicating protection against mitochondrial dysfunction and calcium dysregulation. ASX upregulated Nrf2 and HO-1 expression and restored the BCL2/BAX balance, suggesting inhibition of mitochondrial-mediated apoptosis. Additionally, ASX significantly attenuated CPF-induced anti-angiogenic effects in the in ovo Hen’s Egg Test Chorioallantoic Membrane (HET-CAM) assay. These findings demonstrate, for the first time, that ASX exerts a broad spectrum of protective effects against CPF-induced cytotoxicity in lung cells, mainly through the stabilization of mitochondrial redox status and modulation of apoptosis- and inflammation-related gene pathways, highlighting ASX as a promising candidate for further therapeutic development. Furthermore, the pronounced efficacy observed in the pretreatment regimen suggests that ASX can be evaluated as a potential nutritional preventive strategy in high-risk populations with occupational or environmental CPF exposure. Full article

This study investigates the potential of transient potentiometric signals generated by an array of ion-selective electrodes (ISEs) as the basis for a potentiometric electronic tongue capable of identifying and quantifying a range of inorganic and organic cations. Six distinct polymeric membrane ISEs were fabricated, differing in plasticizer type (either NPOE or DEHS), and in the presence or absence of a lipophilic ion exchanger (KTClPB) and/or an ionophore (DB18C6). Transient potential responses were recorded following the exposure of the electrode array to various cations at different concentrations. A total of 810 transient signals were analyzed through visual inspection and principal component analysis (PCA), revealing characteristic dynamic patterns influenced by membrane composition, ion type, and ion concentration. PCA was conducted both on the transient signals from each individual electrode and on the aggregated dataset comprising signals from the full six-electrode array (electronic tongue). The electronic tongue exhibited a markedly enhanced capacity for discriminating and quantifying ion concentrations in comparison to any single electrode. Full article

Background/Objectives: Copper levels are significantly elevated in both the sera and tumor tissues of various cancers, including prostate cancer. It has therefore been suggested that targeting the elevated copper levels with copper chelators could lead to selective cancer treatment. Thus, several classes of low molecular weight copper-coordinating lipophilic compounds, as well as the newly developed copper complexes of appropriately functionalized polymers, are being investigated as promising novel anticancer therapeutics. Particularly, metal-containing polymers, or metallopolymers, are systematically investigated as anticancer agents or as drug delivery systems. This study aims to utilize the strong copper-chelating properties of hyperbranched polyethyleneimine (PEI) to develop PEI:Cu metallopolymers and evaluate their selectivity and anticancer properties against several prostate cancer cell lines. Methods: A series of PEI:Cu complexes at PEI/Cu ratios that ensure that no free copper ions are present in the solution are prepared and investigated against a human non-cancerous cell line and three prostate cancer cell lines of increasing metastatic potential. Results: PEI:Cu derivatives are cytotoxic against the human prostate carcinoma metastatic PC3 and DU145 cell lines, even at the lowest tested concentrations of 5 μg/mL, while against the non-cancerous HEK293 cells, all metallopolymer derivatives exhibit insignificant cytotoxicity up concentrations of 50 μg/mL. Their cytotoxic effect is associated with mitochondria membrane potential loss and ROS production increase. Conclusions: Hyperbranched polyethyleneimine–coordinated copper(II) metallopolymers, at low concentrations, selectively induce cytotoxicity in metastatic prostate cancer cell lines without compromising the viability of non-cancerous embryonic kidney cells. Full article

Cancer has recently been proposed as a type of channelopathy due to the aberrant expression of various ion channels. Voltage-gated potassium (K⁺) channels (VGKCs) are notably upregulated during tumor proliferation, while voltage-gated sodium (Na⁺) channels are predominantly associated with the invasive stage of cancer progression. Among these, the Kv10.1 channel has been found to be overexpressed in breast cancer, making it a promising therapeutic target. 4-Aminopyridine (4-AP), a non-selective voltage-gated potassium channel blocker, has emerged as a potential novel agent for breast cancer treatment. In this study, we aimed to elucidate the mechanism of action of 4-aminopyridine in breast cancer cells. To investigate the involvement of various cell death pathways, cycloheximide (CHX) (a paraptosis inhibitor), Z-VAD-FMK (a pan-caspase inhibitor), and 2-Aminoethoxydiphenyl borate (2-APB) (a phosphoinositide 3-kinase [PI3K] inhibitor) were employed. Experiments were conducted using the MCF-7 human breast cancer cell line and the L929 mouse fibroblast cell line as a healthy control. Assessments included cell viability assays, intracellular calcium (Ca²⁺) and K⁺ concentration measurements, and plasma membrane potential analysis. Our findings aim to contribute to the understanding of the therapeutic potential and cellular effects of VGKC blockers, particularly 4-aminopyridine, in breast cancer treatment strategies. Full article

Ion-exchange membranes (IEMs) are widely used in reverse-electrodialysis (RED) technology, which can collect the salinity gradient energy between concentrated and diluted solutions and convert it into electromotive force (EMF) to drive power generation and hydrogen production. Recent studies have indicated that the permselectivity of IEMs is vital to determining the performance of an RED stack. In this study, the influences of solution concentration, ion species, and solution temperature on the permselectivity of IEMs were experimentally investigated. The results demonstrate that the permselectivity of IEMs decreases with increasing concentrations of KAc, LiCl, and LiBr solutions for both concentrated solutions (3–5 M) and dilute solutions (0.02–0.2 M). Further, through comparing the LiBr and KBr solutions as well as the LiCl, KCl, and NH₄Cl solutions, respectively, K⁺ demonstrates a higher permselectivity than Li⁺, and both of which are smaller than NH₄⁺ under the same cation and concentration conditions. Moreover, another test was conducted using three potassium salt solutions with different anions, and the experimental permselectivity order is Ac⁻ > Br⁻ > Cl⁻. A slight increase in solution temperature enhances the permselectivity of IEMs due to the increase in ionic mobility. However, an excessive temperature is detrimental to membrane stability and thus reduces permselectivity. It can be seen that ions with low hydration energy, a small hydration radius, and high mobility show a higher permselectivity. Full article

Background Plasma membrane proteins (PMPs) play key roles in cell signalling, adhesion, and trafficking, and are attractive therapeutic targets in cancer due to their surface accessibility. However, their typically low abundance limits detection by conventional proteomic approaches. Methods: To improve PMP detection, we employed a surface proteomics workflow combining cell surface biotinylation and affinity purification prior to LC-MS/MS analysis in cervical (SiHa) and bladder (UMUC3) cancer cell lines cultured under normoxic (21% O₂) or hypoxic (0.1% O₂) conditions. Results: In SiHa cells, 43 hypoxia-upregulated proteins were identified exclusively in the biotin-enriched fraction, including ITGB2, ITGA7, AXL, MET, JAG2, and CAV1/CAV2. In UMUC3 cells, 32 unique upregulated PMPs were detected, including CD55, ADGRB1, SLC9A1, NECTIN3, and ACTG1. These proteins were not observed in corresponding whole-cell lysates and are associated with extracellular matrix remodelling, immune modulation, and ion transport. Biotinylation enhanced the detection of membrane-associated pathways such as ECM organisation, integrin signalling, and PI3K–Akt activation. Protein–protein interaction analysis revealed links between membrane receptors and intracellular stress regulators, including mitochondrial proteins. Conclusions: These findings demonstrate that surface biotinylation improves the sensitivity and selectivity of plasma membrane proteomics under hypoxia, revealing hypoxia-responsive proteins and pathways not captured by standard whole-cell analysis. Full article