Surface Modification Research Articles

Probing Single-Cell Adhesion Kinetics and Nanomechanical Force with Surface Plasmon Resonance Imaging.

Single cell adhesion plays a significant role in numerous physiological and pathological processes. Real-time imaging and quantification of single cell adhesion kinetics and corresponding cell-substrate mechanical interaction forces are crucial for elucidating the cellular mechanisms involved in tissue formation, immune responses, and cancer metastasis. Here, we present the development of a plasmonic-based nanomechanical sensing and imaging system (PNMSi) for the real-time measurement of single cell adhesion kinetics and associated nanomechanical forces with plasmonic tracking and monitoring of cell-substrate interactions and the accompanying nanoscale fluctuations. Both the slow binding and dynamic nanomechanical interaction processes were tracked and analyzed with a thermodynamic model to determine the adhesion kinetic parameters and quantity the mechanical forces. To demonstrate the capabilities of the PNMSi platform, we examined single cell binding interactions across four different surface modifications, and obvious alterations in binding kinetics and corresponding nanomechanical forces were observed, influenced by surface charges and interfacial hydrophilicity. Additionally, we investigated changes in mechanical interaction forces of single cells during cytoskeleton modification, revealing the cross-linking-induced cell adhesion changes. Furthermore, to demonstrate the application capability of the system, the adhesion profiling of primary tumor and metastatic tumor cells was explored, and obvious alterations were observed in the kinetic forces of single cell-substrate interaction. The PNMSi platform facilitates high-throughput single cell adhesion imaging and the quantification of adhesion interaction kinetics and nanomechanical forces with high sensitivity and serves as a promising platform for identifying biomarkers for tumor metastasis and for screening potential therapeutic agents.

A Versatile Ionic Liquid Additive for Perovskite Solar Cells: Surface Modification, Hole Transport Layer Doping, and Green Solvent Processing.

Hole-transport layers (HTL) in perovskite solar cells (PSCs) with an n-i-p structure are commonly doped by bis(trifluoromethane)sulfonimide (TFSI) salts to enhance hole conduction. While lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) dopant is a widely used and effective dopant, it has significant limitations, including the need for additional solvents and additives, environmental sensitivity, unintended oxidation, and dopant migration, which can lead to lower stability of PSCs. A novel ionic liquid, 1-(2-methoxyethyl)-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)amide (MMPyTFSI), is explored as an alternative dopant for 2,2',7,7'-tetrakis(N,N-di-p-methoxyphenylamino)-9,9'-spirobifluorene (spiro-OMeTAD). MMPy ions act as a surface passivator, reducing defects on the perovskite surface, while TFSI ions facilitate p-type doping. MMPyTFSI functions as an efficient dopant, maintaining excellent performance even when tetrahydrofuran (THF) is utilized as a solvent in place of chlorobenzene (CB), while significantly reducing the environmental impact of the process. The optimized PSC achieves a power conversion efficiency (PCE) of 23.10% and demonstrates enhanced long-term stability in all aging tests for over 1000 h in a humid atmosphere, at high temperature, and under simulated sunlight illumination. These results demonstrate that MMPyTFSI is an effective and environmentally friendly dopant for producing stable and efficient PSCs.

Facile Synthesis of Monodisperse Gold Nanorods, Gold Nanobipyramids and Gold Nanocups with Different Coatings and Evaluation of Their Cellular Cytotoxicity.

Assessing the cytotoxicity of gold nanoparticles (GNPs) has gained importance due to their development in the biomedical field. In this study, we systematically synthesized gold nanorods (GNRs), gold nanobipyramids (GNBPs), and gold nanocups (GNCs) using a seed-mediated method, with an average length of 32.53 ± 4.67 nm, 72.90 ± 7.54 nm and 118.01 ± 11.02 nm, respectively. Furthermore, using the cell counting kit-8 (CCK-8) assay, we assessed the cellular cytotoxicity of three different types of GNPs with various different surface coatings, such as organic cetyltrimethylammonium bromide (CTAB) and polyethylene glycol (PEG). The results showed that the cytotoxic behavior of GNPs was shape-dependent in the concentration range of 3.125 -100 μg/mL. The types of GNPs and their surface coating had a significant impact on how the GNPs behaved in cells. Compared to PEG-coated GNPs, which do not induce cell injury, CTAB-coated GNPs show more noticeable cytotoxicity. Furthermore, compared to GNCs, the toxicity of GNRs and GNBPs against GES-1 cells, RAW 264.7 cells and LX-2 cells was greater. Our research provides an important new understanding of the effects of surface modification on the biocompatibility and the shape of GNPs in the biomedical field.

Platinum nanoparticles in cancer therapy: chemotherapeutic enhancement and ROS generation.

Platinum nanoparticles (PtNPs) offer significant promise in cancer therapy by enhancing the therapeutic effects of platinum-based chemotherapies like cisplatin. These nanoparticles improve tumor targeting, reduce off-target effects, and help overcome drug resistance. PtNPs exert their anti-cancer effects primarily through the generation of reactive oxygen species (ROS), which induce oxidative stress and apoptosis in cancer cells. Additionally, PtNPs interact with cellular signaling pathways such as PI3K/AKT and MAPK, sensitizing cancer cells to chemotherapy. Advances in PtNP synthesis focus on optimizing size, shape, and surface modifications to enhance biocompatibility and targeting. Functionalization with biomolecules allows selective tumor delivery, while smart release systems enable controlled drug release. In vivo studies have shown that PtNPs significantly inhibit tumor growth and metastasis. Ongoing clinical trials are evaluating their safety and efficacy. This review explores PtNPs' mechanisms of action, nanotechnology advancements, and challenges in biocompatibility, with a focus on their potential integration into cancer treatments.

Enhancing the biological characteristics of aminolysis surface-modified 3D printed nanocomposite polycaprolactone/nanohydroxyapatite scaffold via gelatin biomacromolecule immobilization: An in vitro and in vivo study.

The surface characteristics of scaffolds utilized in bone tissue engineering profoundly influence subsequent cellular response. This study investigated the efficacy of applying a gelatin coat to the surface of aminolysis surface-modified scaffolds fabricated through 3D printing with a polycaprolactone/hydroxyapatite nanocomposite, employing the hot-melt extrusion FDM technique. Initially, aminolysis surface modification using hexamethylenediamine enhanced surface hydrophilicity by introducing amine functional groups. Subsequently, gelatin solutions were applied to the scaffolds, and crosslinking with EDC/NHS was performed to increase coating strength. Contact angle measurements revealed a significantly increased surface hydrophilicity post-aminolysis. Aminolysis facilitated uniform gelatin coating formation and distribution. Subsequently, crosslinking enhanced coating durability. The addition of gelatin coating resulted in a notable 20 % increase in scaffold mechanical strength and more than 50 % rise in Young's modulus and exhibited enhancement of biodegradability and bioactivity. Gelatin coated scaffolds also demonstrated improved cell viability and adhesion and over two times higher expression of OPN and ALP genes, suggesting improved biological properties. In addition, in vivo bone formation studies verified the biological enhancement of scaffolds. Utilizing an immobilized crosslinked gelatin biomacromolecule coating effectively enhanced the biological characteristics of 3D printed scaffolds and their potential applications as bone tissue engineering scaffolds.

Application of Plasma Spraying Technology in Surface Modification of Orthopedic Implants

Application of Plasma Spraying Technology in Surface Modification of Orthopedic Implants

Experimental investigation and molecular dynamics simulations of plasma treatment on the interface properties of carbon fiber-reinforced PI resin composites

ABSTRACT This paper examines surface modification of carbon fibers using low-temperature plasma and investigates the temperature-dependent interfacial properties of high-performance polyimide-based composites. Additionally, the mechanisms by which air and argon plasma treatments enhance the high-temperature interfacial properties of carbon fiber-reinforced polymers (CFRP) are examined. First, the changes in physical morphology and surface structural defects of carbon fibers under different plasma atmospheres are discussed: carbon fibers develop surface protrusions after various plasma treatments, and a grooved morphology forms after argon plasma treatment. The ID/IG ratio (R value) of the carbon fiber surface increased from 1.25 in untreated fibers to 1.37 after air plasma treatment, and further to 1.60 after argon plasma treatment. The short-beam shear strength test results show that at 300°C, the ILSS (interlaminar shear strength) of argon plasma-treated laminates increased from 67.70 MPa to 87.69 MPa, a 29.53% improvement. The ILSS of air plasma-treated laminates reached 81.46 MPa, a 20.33% improvement. Argon plasma-treated laminates showed more stable interlaminar shear performance at high temperatures, maintaining an interfacial retention rate of 85.11% at 300°C. Secondly, the mechanisms by which air and argon plasma modification enhance the high-temperature interface performance of CFRP are as follows: Air treatment, due to the dual effects of chemical bonding and physical etching, allows the laminated plates to exhibit excellent performance at room temperature. However, in high-temperature environments, the chemical bonding effect is easily affected and damaged, significantly reducing the interface retention rate of the laminated plates. The etching effect of argon treatment is quite significant, which means that the improvement effect of argon mainly manifests in the mechanical interlocking action, with the chemical bonding effect being relatively small. The physical effect of mechanical interlocking is less influenced by temperature, thus the high-temperature retention rate of the laminate is relatively high. Furthermore, molecular dynamics models of the interface were built using atomic simulation to explore how plasma modification introduces active groups that enhance the interface at the molecular level. The impact of these modifications on interfacial structure and energy was analyzed using molecular dynamics metrics. Both experimental and molecular dynamics simulation results confirm that plasma treatment has a positive regulatory effect on the interface.

Design of Polydopamine@iron Oxide-Coated Ammonium Perchlorate Core-Shell Composites for Enhancing the Combustion Performance of HTPB-Based Propellants.

An ammonium perchlorate (AP) composite system with double-coating encapsulation based on the interfacial polymerization behavior of dopamine (DA) in Pickering emulsions was designed to enhance the combustion performance of HTPB-based propellants. The composite system proved highly effective in mitigating the agglomeration issues associated with iron oxide nanoparticles (Fe2O3 NPs) as catalysts, with the AP exhibiting superior performance compared to the composite comprising pure Fe2O3 NPs. The results of the thermal decomposition experiments showed that the HTD temperature of AP@PDA@Fe2O3 was reduced to 318.8 °C, accompanied by a 183.8% increase in heat release and an approximately 30.0% decrease in the activation energy. The combustion rate of AP@PDA@Fe2O3/HTPB was enhanced by approximately 3.0 times higher than that of AP/HTPB. Furthermore, experimental results on safety and surface hydrophobicity showed that the impact sensitivity of the composite AP increased by 28.6%, while the water contact angle was markedly elevated. The reason for the performance enhancement was the synergistic catalytic effect of PDA/Fe2O3 on AP and the dense double-coated structure. This study provided a new idea for the multilevel surface modification of other energy-containing materials.

Technical Routes to Achieve High Circular Polarized Luminescence in Chiral Perovskites: A Mini‐Review

AbstractChiral hybrid organic‐inorganic perovskites (HOIPs) have emerged as promising materials for optoelectronic and spintronic applications, leveraging unique properties such as circularly polarized luminescence (CPL), circularly polarized nonlinear optical (NLO) emission, and chiral‐induced spin selectivity (CISS). However, challenges remain in stabilizing these materials under environmental stresses and precisely controlling chirality for scalable use. This review summarizes five main strategies to induce chirality in HOIPs, i.e., direct incorporation of chiral cations, surface modification with chiral ligands, ion doping, template‐induced chirality, and chiral metasurfaces. Each approach offers distinct advantages for optimizing CPL efficiency and device stability, paving the way for next‐generation applications in CPL detectors, information encryption, spintronic devices, etc.

Stable Antifouling and Antibacterial Coating Based on Assembly of Copper-Phenolic Networks.

Biofilm formation on medical devices has become a worldwide issue arising from its resistance to bactericidal agents and presenting challenges to eradicating biofouling adhesion, especially in biological fluids. Metal-phenolic networks have been demonstrated as a versatile and efficient strategy to prevent biofilm formation by endowing medical devices with prolonged antifouling and antibacterial activities in a one-step surface modification. In this study, we report a simple and environmentally friendly method using coordination chemistry between copper ions (Cu2+) and dopamine-containing copolymer to fabricate metal-phenolic network-based coatings. The phenolic groups also imparted the adhesion of glycopolymer-containing dopamine residues to inorganic and organic substrates, resulting in dual antifouling and bactericidal surfaces. 2-gluconamidoethyl methacrylamide monomer (GAEMA) was first copolymerized with dopamine methacrylamide (DMA) using a free-radical polymerization process. The resulting copolymer (GAEMA-DMA), denoted as GADMA, was then mixed with copper ions in a one-step process to form the GADMA-Cu coating. The GADMA-Cu coating was hydrophilic and significantly reduced the water contact angle (WCA) and adsorption of bovine serum albumin protein even after incubation in a bovine serum albumin solution for 30 h. Moreover, the coating exhibited strong antibacterial activity against Escherichia coli and Staphylococcus aureus and was biocompatible with 99% cell viability toward normal human fibroblast (HDFa) cells. Thus, our coating shows great potential for application in medical devices.

Quantitative Study on the Charge-Dependent Uptake of Ultrasmall Fluorescent Gold Nanoclusters in 3D Spheroids of Cancer Cells.

Gold nanoclusters (AuNCs) have garnered significant attention in biomedical applications, particularly in biosensing, cancer therapy, and imaging, due to their unique optical property, good biocompatibility, and distinct bioactivity. Understanding the cellular uptake behavior of AuNCs is critical to improve the efficacy of their applications, whose mechanism has not been adequately validated. In this work, we synthesized AuNCs with varying surface modifications to quantify the exact law of surface charge on the cellular uptake of AuNCs in a multidimensional manner by using 3D multicellular tumor spheroids of both HeLa cells and MCF-7 cells as the model system. By the combined use of fluorescence live cell imaging and inductively coupled plasma-mass spectrometry, we systematically investigated the effect of surface charge on their uptake rate, intracellular versus intercellular distribution, and penetration depth in a quantitative manner. Our results showed that the cellular uptake of AuNCs was strongly charge dependent, with uptake efficiency increasing with the degree of surface positive charges. A similar charge-dependent uptake behavior was observed in both 2D cell cultures and 3D multicellular tumor spheroids, but the difference in 3D spheroids was less pronounced, in comparison to the 2D model. The effect of AuNCs' surface charge on the cellular uptake has been quantified in multiple dimensions in this work, which also provides crucial knowledge for effective cancer therapeutics and imaging applications based on AuNCs and other nanomaterials.

Study on the properties of biomass carbon quantum dots modified with diamine compounds and their application in iron ion detection

Diamine compounds are widely used as surface modifiers in the functionalization of carbon quantum dots, yet the effects of different diamines on the properties of carbon quantum dots remain unclear. In this study, carbon dots (P-CDs) were synthesized from peanut shell powder via a simple one-step microwave-assisted hydrothermal method. The surface of these carbon dots was modified through co-heating with ethylenediamine (EDA), o-phenylenediamine (OPD), m-phenylenediamine (MPD), and p-phenylenediamine (PPD). The effects of different diamines on the morphology and optical properties of P-CDs were systematically analyzed. The diamine-modified P-CDs exhibited varying sizes and similar crystal structures, with significantly enhanced fluorescence and quantum yields, reaching 35.2% for EDA-CDs. EDA-CDs and OPD-CDs demonstrated excitation-dependent emission behavior, while MPD-CDs and PPD-CDs did not. Based on EDA-CDs, a probe with high sensitivity for Fe3+ was developed, showing a good linear response within the Fe3+ concentration range of 20–100 μM and a detection limit of 2.768 μM. Additionally, the ion probe exhibited a recovery rate of 100.85% in both deionized and tap water, indicating good practical applicability. This study provides essential guidance for the nitrogen surface modification of biomass-derived carbon quantum dots and presents a promising Fe3+ probe with potential applications.

Yellow fluorescent UV-curable epoxy acrylate/VTMS-modified GQDs coatings: study of UV-blocking and viscoelastic properties

Polymer coatings decompose in the presence of UV radiation from sunlight and beget economic and environmental losses. Hence, it is necessary to reinforce the polymer coatings with UV-blocking nanoparticles and to convert the UV light into visible light. In this research work, the surface of graphene quantum dots (GQDs) was modified by vinyltrimethoxysilane (VTMS). VTMS-modified GQDs (VmGQDs) including 0, 0.3 and 0.6 wt% were taken into account to synthesize UV-curable epoxy acrylate/VmGQDs (Ep/VmGQDs) nanocomposite coatings. Surface modification, UV-blockage, fluorescence features and viscoelastic properties of Ep/VmGQDs coatings were analyzed by various spectrometry tests. The existence of VmGQDs (0.3 wt% and 0.6 wt%) in the polymer matrix led to absorption of UV rays in UV regions and fluorescence emission in the visible area with 578 nm wavelength (yellow fluorescence). Appearance of strong absorption bands at 250, 285 and 365 nm by the coatings with VmGQDs confirmed that a large portion of UV rays was absorbed and blocked. The intensity of UV-blockage by Ep/VmGQDs 0.6 wt% was recorded >99%. Furthermore, reinforcement of the coatings with VmGQDs resulted in increase in storage modulus, cross-linking density and Tg value.

Harnessing the power of microbial fuel cells as pioneering green technology: advancing sustainable energy and wastewater treatment through innovative nanotechnology.

The purpose of this review is to gain attention about intro the advanced and green technology that has dual action for both clean wastewater and produce energy.Water scarcity and the continuous energy crisis have arisen as major worldwide concerns, requiring the creation of ecologically friendly and sustainable energy alternatives. The rapid exhaustion of fossil resources needs the development of alternative energy sources that reduce carbon emissions while maintaining ecological balance. Microbial fuel cells (MFCs) provide a viable option by producing power from the oxidation of organic and biodegradable chemicals using microorganisms as natural catalysts. This technology has sparked widespread attention due to its combined potential to cleanse wastewater and recover energy. The review presents a complete examination of current advances in MFCs technology, with a focus on the crucial role of anode materials in improving their performance. Moreover, different anode materials and their nanoscale modifications are being studied to boost MFC efficiency. This current review alsofocused on the effects of surface modifications and different anode compositions on power generation and system stability. It also investigates the electrochemical principles behind these enhancements, providing insights into the economic potential of MFCs. MFCs provide a long-term solution to energy and environmental issues by addressing both wastewater treatment and energy production.

Enhancing Carbon Monoxide Tolerance in Low-Temperature PEM Fuel Cells through Carbon Nitride Surface Modification.

Low-temperature proton exchange membrane fuel cells (PEMFCs) reuqire highly pure hydrogen gas due to their extreme sensitivity to carbon monoxide (CO) contamination, which poses a challenge for using cost-effective reformed hydrogen sources. To address this issue, we have developed a surface modification strategy by applying a 0.5-0.91 nm amorphous carbon nitride layer onto PtRu/C substrates. The electrochemical measurements indicate that the modification selectively facilitates hydrogen gas transport to a surface while inhibiting carbon monoxide diffusion. The kinetic studies of CO adsorption reveal that the surface modification significantly reduces CO adsorption, effectively halving the rate compared to conventional catalysts. Additionally, rotating disk electrode experiments show that the catalyst modified with amorphous carbon nitride layer maintains stable operation for over 20 h with 1000 ppm of CO/H2. Furthermore, it supports stable discharge at 1 A cm-2 in PEMFCs with up to 10 ppm of CO, a concentration far exceeding the widely accepted standard of 0.2 ppm.

Hydrogel Electrolyte-Mediated In Situ Zn-Anode Modification and the Ru-RuO2/NGr-Coated Cathode for High-Performance Solid-State Rechargeable Zn-Air Batteries.

This work aims to deal with the challenges associated with designing complementary bifunctional electrocatalysts and a separator/membrane that enables rechargeable zinc-air batteries (RZABs) with nearly solid-state operability. This solid-state RZAB was accomplished by integrating a bifunctional electrocatalyst based on Ru-RuO2 interface nanoparticles supported on nitrogen-doped (N-doped) graphene (Ru-RuO2/NGr) and a dual-doped poly(acrylic acid) hydrogel (d-PAA) electrolyte soaked in KOH with sodium stannate additive. The catalyst shows enhanced activity and stability toward the two oxygen reactions, i.e., oxygen reduction and evolution reactions (ORR and OER), with a very low potential difference (ΔE) of 0.64 V. The computational insights bring out the electronic factors contributing to the enhanced catalytic activity of Ru-RuO2/NGr based on the charge density difference (CDD) between the interfaces. The disadvantages of the existing solid-state RZABs, such as their limited lifespan brought on by passivation, dendritic growth, corrosion, and shape change, have also been taken into account. The introduction of the stannate additive to the electrolyte induced an in situ Zn-anode modification, which subsequently improved the interfacial stability of the ZABs and, hence, the battery life cycles. The experimental observations reveal that, during the charging process, the Sn nanoparticles enable the homogeneous Zn deposition on the surface of the anode. Thus, the in situ Zn-anode surface modification assisted in achieving a high-rate cycle capability, viz., the homemade catalyst-based system exhibited continuous charge-discharge cycles for 20 h at a current density of 2.0 mA cm-2, with each cycle lasting for 5 min.

Substantially Improving CO2 Permeability and CO2/CH4 Selectivity of Matrimid Using Functionalized-Ti3C2Tx.

Mixed-matrix membranes (MMMs) with favorable interfacial interactions between dispersed and continuous phases offer a promising approach to overcome the traditional trade-off between permeability and selectivity in membrane-based gas separation. In this study, we developed free-standing MMMs by embedding pristine and surface-modified Ti3C2Tx MXenes into Matrimid 5218 polymer for efficient CO2/CH4 separation. Two-dimensional Ti3C2Tx with adjustable surface terminations provided control over these critical interfacial interactions. Characterization (Raman spectroscopy, XPS, DSC, FTIR) indicated the formation of hydrogen bonds between the termination groups on Ti3C2Tx and the carbonyl groups of Matrimid, promoting enhanced compatibility and dispersion of MXenes within the polymer matrix. The resulting MMMs with 5 wt % Ti3C2Tx showed a 67% increase in CO2 permeability and an 84% enhancement in CO2/CH4 selectivity compared to pristine Matrimid membranes. Surface modification of Ti3C2Tx using [3-(2-aminoethylamino)propyl]trimethoxysilane (AEAPTMS) further enhanced compatibility, leading to MMMs with 140% higher CO2 permeability and 130% greater CO2/CH4 selectivity. Molecular simulations suggested that AEAPTMS functionalization improved interfacial interactions with Matrimid chains, increasing the affinity of MXenes toward CO2 molecules. Additionally, the elongation of gas pathways, polymer chain disruption, and the presence of interlayer nanogalleries contributed positively to the enhanced separation performance. This work provides insights into tailoring nanomaterial-polymer interfaces to address the challenges of gas separation, paving the way for environmentally friendly CO2 separation technologies.

Research progress on surface modification and coating technologies of biomedical NiTi alloys.

NiTi alloys are an important class of biomaterials with extensive clinical applications such as cardiovascular stents, orthodontic arch-wires, esophageal stents, orthopedic implants and more. However, the long-term implantation of NiTi alloys presents significant challenges due to their susceptibility to wear, corrosion and the excessive release of harmful nickel ions. These factors can severely compromise both the biocompatibility and the overall service life of the implants. To better meet the demands for safety, durability and superior biological performance after implantation, surface modification of NiTi alloys has become a focal point of current research. Based on the fundamental properties of the NiTi alloys and the challenges encountered in their practical applications, this article provides a focused review of recent advances in improving their corrosion resistance, wear resistance, antibacterial properties and biological performance through surface modification and coating techniques. In addition, the paper outlines current research challenges and proposes recommendations for future development directions.

Effect of laser remelting on the microstructure and properties of an AlCoFeNi eutectic high-entropy alloy fabricated through double-wire arc additive manufacturing

Additive manufacturing (AM) technology is a new method for preparing eutectic high-entropy alloys (EHEAs). The resulting EHEAs have excellent mechanical properties. However, in engineering, material failure, such as wear or fatigue fracture, often occurs on the surfaces of components. There is no report on surface modification and strengthening of additively manufactured EHEAs. Therefore, this study successfully utilized laser remelting (LR) technology to enhance the surface properties of an AlCoFeNi EHEA fabricated by using double-wire arc AM technology. After LR, the distance between adjacent regular eutectic regions and lamellar spacing of the EHEAs significantly decreased, and the proportion of strictly semicoherent face-centered cubic/body-centered cubic interfaces increased. When microhardness increased from 277.7 HV to 302.3 HV, the average friction coefficient and wear rate of the alloys decreased by 32.5% and 51.1%, respectively, and hardness and wear resistance significantly improved. This study has laid a solid foundation for the engineering application of the combination of LR and AM and also provided new ideas for improving the surface performance of additively manufactured EHEAs.

Modeling and optimization of surface modification process of ultrafiltration membranes by guanidine-based deep eutectic solvent.

Low performance and the high fouling tendency of Polyetherimide (PEI) membranes prevent their widespread commercial utility. In this study, we utilized a deep eutectic solvent (DES) as a versatile agent for surface modification of the PEI membrane using a simple and sustainable method. To attain an efficient PEI membrane, modeling and optimization of the modification condition were conducted via response surface methodology (RSM). The effects of two effective variables, including the choline/guanidine (Ch/Gu) ratio (0.5-2) and modification time (12-48h), were evaluated on four responses, i.e., pure water flux (PWF), flux recovery ratio (FRR), irreversible fouling ratio (Rir), and total resistance (Rt). The structural and chemical characteristics and filtration performance of the fabricated membranes were evaluated. The optimum condition was obtained at a 0.8 Ch/Gu ratio and 30h of modification time to reach the best performance of the DES-PEI membrane. The industrial application of optimally modified DES/PEI membrane was investigated by filtering penicillin and cephalexin antibiotics. The rejection data showed higher performance of the modified membrane (>95%) compared to the bare membrane (∼63%). Furthermore, the long-term filtration evaluation in dead-end and cross-flow setups indicated stable flux and rejection of the DES/PEI-modified membrane. The DES, including Ch/Gu, can be viewed as an agent to enhance both PWF and antifouling properties while broadening membrane applications in separating antibiotics for PEI membranes through an eco-friendly and cost-effective method.