Hydrophobicity Stability Research Articles

Pea protein isolate-soluble soybean polysaccharides electrostatic assembly: effect of pH, biopolymer mass ratio and heat treatment.

In past years, thousands of protein-polysaccharide complexes have been investigated to modify protein characteristics and functionality in food systems. However, the interaction between pea protein isolate (PPI) and soluble soybean polysaccharide (SSPS) has not been thoroughly characterized yet. In the present study, the phase behavior of PPI and SSPS mixtures was analyzed as a function of PPI:SSPS mixing ratio (1:1 to 1:0.10) and pH (7.0 to 2.0), showing that these biopolymers could be electrostatically assembled at 1:1 to 1:0.25 mixing ratios and 4.0 to 3.0 pH values. Then, the characteristics of the PPI-SSPS complexes were studied before and after heating (90 °C and 30 min) by ζ-potential, surface hydrophobicity, protein solubility, particle size distribution and physical stability for 56 days. By lowering the pH and PPI:SSPS mixing ratio, the complexes showed increased solubility, changed 𝜁-potential and higher physical stability. By heating, the complexes presented increased hydrophobicity and physical stability. Overall, PPI-SSPS complexes increased the protein solubility, reduced the particle size, and changed both the ζ-potential and the surface hydrophobicity with respect to PPI control, allowing stabilization of the colloidal system and broadening the possible applications of these high-quality proteins in acidic food systems. © 2024 Society of Chemical Industry.

Wood dimensional stability enhancement by multivalent metal-cation-induced lignocellulosic microfibrils crosslinking

Wood is a hygroscopic material that responds to the moisture changes of the surrounding environment through swelling and shrinkage, making it dimensionally unstable. Here, we introduce a facile metal-ion-modification (MIM) approach to enhance the dimensional stability of wood. The MIM process involved swelling the wood samples with aqueous metal ion solutions and drying. The high valent metal cations, such as Fe3+, Al3+, and Zr4+, interacted with the hydrophilic groups (e.g., OH, COOH) present in the wood fibers, limiting their access to water and moisture, thereby enhancing the wood's hydrophobicity and dimensional stability. Evaluation of three wood species, southern yellow pine, poplar, and red oak, revealed water contact angles of 120–130° after MIM, indicative of enhanced surface hydrophobicity. Fe3+ treatment decreased southern yellow pine's swelling ratio from 6 % to 4 %. Fe3+-treated wood exhibited tangential anti-swelling efficiencies ranging from 39.83 % to 57.14 % and radial anti-swelling efficiencies from 34.74 % to 48.33 %, varying across wood species. The enhancement of wood dimensional stability can be attributed to the formation of irreversible coordination bonds between metal cations and lignocellulosic microfibrils in the wood cell wall. These bonds prevent the microfibrils from slipping in response to moisture absorption and desorption.

Benzoxazine/ thermoplastic polyurethane nanofibrous membranes with superior mechanical properties for efficient oil-water separation

The integration of membrane separation and electrospinning technologies has significantly advanced oil-water separation processes. However, enhancing the mechanical robustness, corrosion resistance, and durability of oil-water separation membranes remains a challenge. In this paper, we utilized the electrospinning technique to fabricate a micro-nanostructured nanofibrous (NFs) membrane by blending benzophenone monomer (BPAF-an) with thermoplastic polyurethane elastomer (TPU). By optimizing the solid content, the mass ratio of compounds to polymers, and the solvent composition in the spinning precursor solution, we determined the optimal electrospinning parameters for fabricating the TPU/BPAF-an NFs membrane. The incorporation of BPAF-an, known for its low surface energy, significantly enhanced the hydrophobicity of the nanofiber membrane. The TPU/BPAF-an NFs membrane demonstrated excellent mechanical properties, exhibiting a tensile strength of 7.38 MPa and an elongation at break of 292 %. The membrane had good hydrophobicity and its water contact Angle is up to 145.2°. It also displayed exceptional separation efficiency, exceeding 99 % for oil-in-water emulsions and various oil-water mixtures. Even in harsh environments such as strong acids, alkalis and salts, they have prominent hydrophobicity, lipophilicity and chemical stability. In addition, the membrane maintained a high flux rate of 1995.37 L m−2 h−1 and a separation efficiency of 96 % even after 100 cycles of oil-water separation. Consequently, the TPU/BPAF-an NFs membrane, with its superior mechanical properties and cycle stability, holds substantial promise for application in oil-water separation.

Structure and Properties of Exopolysaccharide Produced by Gluconobacter frateurii and Its Potential Applications.

An exopolysaccharide (EPS)-producing bacterium was isolated from apricot fermentation broth and identified as Gluconobacter frateurii HDC-08 (accession number: OK036475.1). HDC-08 EPS is a linear homopolysaccharide mainly composed of glucose linked by α-(1,6) glucoside bonds. It contains C, H, N and S elements, with a molecular weight of 4.774 × 106 Da. Microscopically, it has a smooth, glossy and compact sheet structure. It is an amorphous noncrystalline substance with irregular coils. Moreover, the EPS showed surface hydrophobicity and high thermal stability with a degradation temperature of 250.76 °C. In addition, it had strong antioxidant properties against DPPH radicals, ABPS radicals, hydroxyl radicals and H2O2. The EPS exhibited high metal-chelating activity and strong emulsifying ability for soybean oil, petroleum ether and diesel oil. The milk solidification test indicated that the EPS had good potential in fermented dairy products. In general, all the results demonstrate that HDC-08 EPS has promise for commercial applications as a food additive and antioxidant.

Effect of low-frequency alternating magnetic fields on the physicochemical, conformational and rheological properties of myofibrillar protein after iterative freeze-thaw cycles

In this work, the effects of low-frequency alternating magnetic fields (LF-AMF) on the physicochemical, conformational, and functional characteristics of myofibrillar protein (MP) after iterative freeze-thaw (FT) cycles were explored. With the increasing LF-AMF treatment time, the solubility, active sulfhydryl groups, surface hydrophobicity, emulsifiability, and emulsion stability of MP after five FT cycles evidently elevated and then declined, and the peak value was obtained at 3 h. Conversely, the moderate LF-AMF treatment time can significantly reduce the average particle size, carbonyl content, and endogenous fluorescence intensity of MP. The rheology results showed that various LF-AMF treatment times would elevate the G' value of MP after iterative FT cycles. The FTIR spectroscopy results suggested that LF-AMF influenced the secondary structure of MP after multiple FT cycles, resulting in a depression in α-helix content and an increment in β-folding proportion. Moreover, LF-AMF treatment induced the gradually lighter and wider myosin heavy chain bands of MP, implying that LF-AMF accelerated the degradation of macromolecular aggregates. Therefore, the LF-AMF treatment efficaciously ameliorates the structural and functional deterioration of MP after iterative FT cycles and could be used as a potential quality-improving technology in the frozen meat industry.

Single‐Atom Nanozyme‐Like Lanthanum Moieties for High‐Performance Electromagnetic Energy Absorption

AbstractSingle‐atom (SA) nanozymes have unprecedented physicochemical performance due to their integrated merits of both atomically dispersed metal atoms and bio‐enzymes. However, the structure‐function relationship between the SA nanozyme‐like structure and its dielectric performance is still unclear. Furthermore, controllable synthesis of SA nanozyme‐like structures remains challenging due to their unique five‐coordinated configurations. Here, a dicyandiamide‐mediated pyrolysis strategy is proposed to anchor five nitrogen‐coordinated lanthanum (La)–N5 moieties on interconnected N‐doped graphene nanocages (La‐N5/ING). Theoretical predictions indicate that the spatially coordinated La–N5 moieties exhibit significantly enhanced conduction loss and polarization loss compared to La–N4 moieties, as evidenced by the experimental results. Moreover, the polydimethylsiloxane‐coated chemically cross‐linked film constructed by the La‐N5/ING and aramid nanofibers has outstanding electromagnetic wave (EMW) absorption performance with an effective absorption bandwidth (EAB10) of 6.24 GHz at a thickness of merely 2.0 mm, outperforming those of most reported carbon‐based films. Importantly, the film also has excellent flexibility, hydrophobicity, mechanical strength, and structural stability, ensuring its application potential in practical environments. These findings provide crucial insights into the microscopic environment of SA on the dielectric properties of their host materials, and a critical method for the preparation of multifunctional films with spatial coordinated SA.

Preparation of SiO2-polydimethylsiloxane-octadecyltrichlorosilane superhydrophobic coating and its self-healing performance

The self-healing performance of superhydrophobic coatings is an important property to enhance the durability and self-cleaning character, which has been a focus of surface modification in recent years. In this work, a simple method was proposed for preparing the superhydrophobic coatings with self-healing properties on slides using nano-SiO2, octadecyltrichlorosilane, and polydimethylsiloxane. The hydrophobic properties, morphologies, compositions, structures, stability, and self-healing properties were respectively investigated via various characterizations and tests. The results indicated that the self-healing properties of the coatings were induced by the Si-O-Si bonds through X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The best self-healing property and hydrophobicity after healing were obtained when the content of polydimethylsiloxane was 35% (wt.), and the contact angle of water would arrive at 160.98° when the concentration of nano-SiO2 was 3% (wt.). The contact angle of each coating surface remained stable and thermally stable when the temperature was increased from 100 to 300 °C ( Tg), and the coatings remained stable under natural acidic and alkaline environments as well as mechanical shocks. So superhydrophobic coatings with self-healing performance have potential applications for the development of durable surfaces.

PMDI cross-linked rare earth/liquid metal reinforced ANF/MXene membranes for multifunctional electromagnetic interference shielding

With the miniaturization of electronic devices, the creation of efficient and lightweight electromagnetic interference (EMI) shielding materials is of imminent significance. In this context, we reported an electromagnetic shielding membrane with hydrophobic, antioxidative, and high temperature stability. The chemically cross-linked Aramid nanofibers (ANF)/MXene@Ga/Gd2O3 (CAMG) nanocomposite membranes exhibit a considerable tensile strength and possess exceptional flexibility. The CAMG shielding membranes demonstrate multiple heterogeneous interfaces and a magnetic-dielectric synergistic system, thereby effectively enhancing the absorption shielding efficiency, with the specific shielding effectiveness per unit volume (SSE/t) reaching 6788 dB cm2 g−1. Furthermore, the composite membranes demonstrate remarkable electrothermal capabilities, acting as pliable heaters with notable, swiftly replicable, and consistent electrothermal effects at reduced voltages. Additionally, they possess superior heat dissipation efficiency and ensure a uniform heat dispersion. The exceptional electromagnetic shielding performance and multifunctionality of the C-ANF/MXene@Ga/Gd2O3 shielding membranes imply their instructive relevance in next-generation fields such as flexible electronics and aerospace.

Abstract 3543: TWNeoDB: A web-based database for tumor neoantigens in the Taiwanese population

Abstract Tumor neoantigens are highly immunogenic. Two types of neoantigens have been reported for their ability to be shared among patients. One is a mutated tumor-specific antigen (mTSA) derived from somatic mutations in tumor cells. The other is an aberrantly expressed TSA (aeTSA), influenced by epigenetic changes or abnormal RNA splicing. Tumor neoantigens can bind with the major histocompatibility complex (MHC) and be recognized by the T cell receptor (TCR). Consequently, they can trigger the immune system to attack cancer cells. Until now, some neoantigen databases have been available, they mostly focus on the Western population and primarily contain peptides derived from mTSAs. In contrast, our database provides peptides not only from mTSA but also from aeTSA with a strong emphasis on the Taiwanese population. Initially, we obtained public sequencing raw data from the NCBI database and employed a neoantigen pipeline for analysis, identifying potential neoantigens. The data collection criteria included samples from Taiwanese individuals, with paired DNA-seq or RNA-seq from both normal and tumor tissues of the same patients. RNA sequencing datasets were utilized to identify aeTSAs and mTSAs, whereas DNA sequencing datasets served for mTSA identification. Additionally, human leukocyte antigen (HLA) genotyping was performed for every sample. The identified peptides were further compared to previously validated data available on IEDB. This data was used to develop a web-based database with several functionalities. Users can search for specific peptides and download relevant data from the website. The website also included data cross-referenced and validated with IEDB. In addition, we incorporated clinically validated peptides capable of stimulating T cells to release cytotoxins or interferons. A machine-learning-based LightGBM model was trained to predict immunogenicity for these peptides through a series of cross-validations based on random data splitting. Users can access comprehensive information on tumor-specific peptides in the online database. We collected sequencing data from 243 patients, spanning five different types of cancer. The predominant HLA genotype is HLA-A*11:01, a common allele in the Taiwanese population. Peptide characteristics, such as hydrophobicity, binding affinity, and binding stability, have been calculated and stored in the database. Notably, the LightGBM model excelled in predicting immunogenicity, achieving an AUC of 0.95 on the training dataset and 0.8 on the testing dataset. Implemented in the online database, this model allows users to forecast their own candidates. The state-of-the-art database serves as a comprehensive platform for gathering Taiwanese-specific neoantigens, contributing to the advancement of personalized cancer vaccines and immunotherapies. Citation Format: Yu-Hsuan Tseng, Chia-Hsin Wu, Chia-Yu Sung, Huang Kevin Chih Yang, Mong-Hsun Tsai, Liang-Chuan Lai, Tzu-Pin Lu, K.S. Clifford Chao, Eric Y. Chuang, Chien-Yueh Lee. TWNeoDB: A web-based database for tumor neoantigens in the Taiwanese population [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 3543.

In-situ growth of CuS on polyimide film to construct dense and continuous network: Achieving excellent electrothermal and EMI shielding performance

The performance of the electrothermal film is generally determined by conductive filler network. However, it is still challenging to construct a dense network of conductive fillers in the electrothermal film. In this work, we develop a simple and efficient method to construct a dense and continuous network via in-situ growth of CuS nanosheets on the surface of polyimide (PI) film with stable interfacial bonding. The obtained PI@CuS electrothermal film is further packaged by commercially available PTFE and PI tapes to achieve desirable surface hydrophobic self-cleaning function and stability for the use in different environments. By tuning the network density of CuS nanosheets, it imparts excellent electrothermal conversion efficiency and cycling stability to the PI@CuS film, whose surface temperature could rapidly ramp up over 200 °C at 8 V. The film also exhibits excellent photothermal performance, reaching close to 100 °C at 100 mW/cm2. The anti-icing/de-icing experiment shows that the icing time is prolonged significantly at low temperature and the melting time is reduced dramatically. Furthermore, the PI@CuS film also exhibits outstanding electromagnetic interference (EMI) shielding effectiveness of 57.1 dB with a thickness of only 80 μm, and excellent tensile strength of over 90 MPa. The in-situ growth strategy provides a novel route for the fabrication of the electrothermal film with excellent overall performance.

Characterization of novel polysulfide polymer coated fly ash and its application in mitigating diffusion of contaminants

Fly ash consists of a considerable amount of hazardous elements with high mobility, posing substantial environmental risks during storage in surface impoundments and landfills. This hinders its efficient reuse in construction or material industries. To enhance the versatility of fly ash applications, a novel surface modification technique, termed SuMo, has been developed to create a hydrophobic polysulfide polymer coating on the surface of fly ash particles. The physicochemical properties of SuMo fly ash samples were examined using atomic force microscopy (AFM), environmental scanning electron microscopy (ESEM), thermal gravimetric analysis (TGA), Fourier Transform Infrared spectroscopy (FTIR), and leaching of hazardous elements was tested under practical environmental conditions (pH 4–12) based on the EPA's leaching environmental assessment framework (LEAF). The successful coating of polysulfide polymer on fly ash surface was verified through an increased percentage of C, S, and O in elemental mapping, coupled with the identification of S–O, CO, and C–H functional groups consistent with the chemical structure of polysulfide polymer. While the SuMo fly ash particles maintained their spherical shape, they exhibited increased surface roughness, robust hydrophobicity, and thermal stability up to 250 °C. Notably, owing to the coating's resilience against water leaching, the SuMo fly ash demonstrated a substantial reduction (up to 60-fold) in leachate concentrations of multiple concerning elements, including B, Be, Ba, Mn, Zn, As, Cr, Hg, etc., under various pH conditions compared to the uncoated fly ash. Furthermore, the polysulphide polymer coating effectively prevented Hg volatilization from fly ash below 163 °C. This study highlights the efficacy of the developed polysulfide polymer coating in mitigating the diffusion of hazardous elements from fly ash, thereby enhancing its potential reutilization in material, construction, and agriculture industries.

Eco-friendly composites with specific functional properties

The development of sustainable hydrophobic composite coatings is of high interest for aircraft applications. Currently, the use of natural derived functionalized microparticles as filler to obtain hydrophobic epoxy-based coatings was not deeply investigated. In this scenario, a novel hydrophobic epoxy-based composite including waste hemp microparticles functionalized with silica layer, 3-aminopropyltriethoxysilane, polypropylene-graft-maleic anhydride and silanes (hexadecyltrimethoxysilane and 1H,1H,2H,2H- Perfluorocotyltriethoxysilane) is presented. The resulting coating was casted on typical aeronautical panel, based on carbon-fiber-reinforced polymers, to achieve an improved hydrophobicity and anti-icing property induced by functionalized hemp microparticles.The wettability and anti-icing property were investigated. Compared to unfilled epoxy resin, the obtained composite coating achieved a greater water contact angle of 30° and doubled increase in icing time. Despite the low content (2 wt.%) of hemp particles, DSC analysis displayed a relevant increase in Tg value, confirming an efficient interaction between the epoxy matrix and the functionalized hemp filler. AFM analysis proved how the presence of hemp filler leads to an increase in roughness due to the hierarchical structure formed by the long chains of silane molecules. The combination of silane activity and rough morphology allows the development of hemp composite coatings with enhanced hydrophobicity, anti-icing behavior and thermal stability for aircraft applications.

Influence of chromium oxide nanoparticles and fiber fillers on silicone rubber nanocomposite

The development of polymer composites, considering the environmental issues, is aimed for minimizing the industrial content. New environmental-friendly nanocomposites, based on silicone rubber matrix and different concentrations of natural fiber/chromium oxide fillers, are prepared for the first time. The microstructural analysis confirms the successful obtaining of microfibers after treatment and chromium oxide nanoparticles and the formation of the final composite. The nanocomposites achieved improved physical and mechanical properties due to the dual effect of both fillers and attachment to the matrix. The 1% optimized nanocomposite achieved the highest modulus, dielectric properties, hydrophobicity, and surface stability. The effect of exposure to weathering conditions was studied. The characterization sentence asserts the preparation of a novel silicone rubber nanocomposite with improved properties, along with the environmental impact, regarding the dual effect of natural fiber waste and chromium oxide nanoparticles.

Icephobic Coating Based on Novel SLIPS Made of Infused PTFE Fibers for Aerospace Application.

The development of slippery surfaces has been widely investigated due to their excellent icephobic properties. A distinct kind of an ice-repellent structure known as a slippery liquid-infused porous surface (SLIPS) has recently drawn attention due to its simplicity and efficacy as a passive ice-protection method. These surfaces are well known for exhibiting very low ice adhesion values (τice < 20 kPa). In this study, pure Polytetrafluoroethylene (PTFE) fibers were fabricated using the electrospinning process to produce superhydrophobic (SHS) porous coatings on samples of the aeronautical alloy AA6061-T6. Due to the high fluorine-carbon bond strength, PTFE shows high resistance and chemical inertness to almost all corrosive reagents as well as extreme hydrophobicity and high thermal stability. However, these unique properties make PTFE difficult to process. For this reason, to develop PTFE fibers, the electrospinning technique has been used by an PTFE nanoparticles (nP PTFE) dispersion with addition of a very small amount of polyethylene oxide (PEO) followed with a sintering process (380 °C for 10 min) to melt the nP PTFE together and form uniform fibers. Once the porous matrix of PTFE fibers is attached, lubricating oil is added into the micro/nanoscale structure in the SHS in place of air to create a SLIPS. The experimental results show a high-water contact angle (WCA) ≈ 150° and low roll-off angle (αroll-off) ≈ 22° for SHS porous coating and a decrease in the WCA ≈ 100° and a very low αroll-off ≈ 15° for SLIPS coating. On one hand, ice adhesion centrifuge tests were conducted for two types of icing conditions (glaze and rime) accreted in an ice wind tunnel (IWT), as well as static ice at different ice adhesion centrifuge test facilities in order to compare the results for SHS, SLIPs and reference materials. This is considered a preliminary step in standardization efforts where similar performance are obtained. On the other hand, the ice adhesion results show 65 kPa in the case of SHS and 4.2 kPa of SLIPS for static ice and <10 kPa for rime and glace ice. These results imply a significant improvement in this type of coatings due to the combined effect of fibers PTFE and silicon oil lubricant.

An investigation on the hydrophobic binding stability of Azithromycin to the hydrocarbon chains of Tween: Based on micellization thermodynamics

Based on micellization thermodynamics, the difference in hydrophobic binding stability between Azithromycin and the hydrocarbon chain of Tween was investigated. Initially, the critical micelle concentration (CMC) of AZM-loaded Tween micelles was determined by measuring surface tension, followed by subsequent analysis and discussion of the associated parameters of micellization thermodynamics. The findings indicated that AZM-loaded Tween 20 and AZM-loaded Tween 80 micelles both exhibited a lower CMC value, enhanced stability at the air/water interface, and a more pronounced tendency towards micellization. This suggested that Azithromycin exhibited a stronger affinity towards the hydrophobic hydrocarbon chains of Tween 20 and Tween 80, leading to a more robust hydrophobic binding between them, thereby promoting the formation of AZM-loaded micelles. Subsequently, the transmittance, particle size, and in vitro release of each micelle system were assessed. The findings demonstrated that both AZM-loaded Tween 20 and AZM-loaded Tween 80 micelles exhibited excellent physical stability. Furthermore, in terms of antibacterial activity, AZM-loaded Tween 20 and AZM-loaded Tween 80 micelles exhibited stronger antibacterial efficacy. In summary, the variation in the hydrocarbon chain of Tween exerts an influence on the stability of the hydrophobic binding between Tween and Azithromycin, consequently impacting the pertinent attributes of drug-loaded micelles. This finding offers a valuable point of reference for the investigation of hydrophobic drug micelles in academic research.

Modeling the behavior of monoclonal antibodies on hydrophobic interaction chromatography resins

Monoclonal antibodies (mAbs) require a high level of purity for regulatory approval and safe administration. High-molecular weight (HMW) species are a common impurity associated with mAb therapies. Hydrophobic interaction chromatography (HIC) resins are often used to remove these HMW impurities. Determination of a suitable HIC resin can be a time and resource-intensive process. In this study, we modeled the chromatographic behavior of seven mAbs across 13 HIC resins using measurements of surface hydrophobicity, surface charge, and thermal stability for mAbs, and hydrophobicity and zeta-potential for HIC resins with high fit quality (adjusted R2 > 0.80). We identified zeta-potential as a novel key modeling parameter. When using these models to select a HIC resin for HMW clearance of a test mAb, we were able to achieve 60% HMW clearance and 89% recovery. These models can be used to expedite the downstream process development for mAbs in an industry setting.Graphical

Thermal-Driven Curcumin Release Film with Dual-Mode Synergistic Antibacterial Behavior for Efficient Tangerine Preservation.

Antimicrobial packing showed great potential in extending the shelf life of food. However, developing a new biocomposite film with an intelligent and efficient antimicrobial performance is still desirable. Herein, a Fe-MoOx encapsulated with curcumin (Cur) filled chitosan-based composite film (CCF films) was prepared by solvent casting method. The total color differences of the CCF films were less than 30%, and satisfactory surface color, transparency, hydrophobicity, and thermal stability were also obtained. Besides, the UV-light/water/oxygen barrier capability and mechanical properties were enhanced with the incorporation of Cur@Fe-MoOx. Moreover, CCF films showed photothermal performance and thermal-controlled curcumin release ability, which endowed the CCF0.15 film with excellent antibacterial capability toward E. coli (≥99.95%) and S. aureus (≥99.96%) due to the synergistic antibacterial effect. Fe-MoOx exhibited high cell viability and less than 5% hemolysis even under the concentration of 500 μg mL-1. Based on those unique characteristics, the CCF0.15 film was chosen for tangerine preservation. The CCF0.15 film could prolong the shelf life of tangerine by at least 9 days compared with the unpacking group, and the tangerines could maintain the freshness characteristics over a 24 day storage period. Such thermal-mediated antibacterial film proposed by our work showed promising potential in food packaging.

Supramolecular immobilization of lipase inspired by octopus suckers for biodiesel production

It is still a challenge to design a supramolecular interaction system for immobilizing enzymes efficiently and stably. In this work, inspired by octopus suckers, we used cyclodextrin with a similar structure to the octopus sucker cavity as supramolecular interaction functional units of soft tentacles to immobilize lipase through physical adsorption. By modifying the surface of cyclodextrin with polar hydrophilic groups, the difference in hydrophilic and hydrophobic properties and stability within the molecule were effectively improved, thereby enhancing the cavity suction of cyclodextrin. The enzyme load of the soft tentacles reached 10 mg/g, and the lipase was adsorbed firmly under high strength mechanical action (the retention rate is 66.4%, other physical adsorption under the same conditions is 51.6%). The soft tentacle immobilized lipase showed good dispersibility in the organic phase and its water absorption characteristics could provide oil-water interface for lipase in organic phase reaction, promoting the forward transesterification reaction. Compared with free lipase, the soft tentacle immobilized lipase (L-CDST-Ms) showed the improved activity, which could reach 180% of that of free lipase. The L-CDST-Ms was applied to biodiesel production, and the conversion rate could reach 94%. The results showed that the immobilization method opened up a new way for the application of lipase in transesterification.

Synthesis and characterization of high-flux ZIF-90/poly-dimethyldiethoxysilane (PDMDES) mixed matrix membrane for enhanced pervaporation recovery of alcohols

In the present research, micron-sized zeolitic imidazolate framework-90 (ZIF-90) particles were synthesized utilizing an adapted synthesis route and subsequently incorporated into the poly-dimethyldiethoxysilane (PDMDES) polymer to fabricate ZIF-90/PDMDES mixed matrix membrane (MMM) with an objective to achieve enhanced pervaporation performance for the efficient separation of alcohols from aqueous solutions. Comprehensive characterization techniques were employed to investigate the properties of the ZIF-90 particles and the newly fabricated ZIF-90/PDMDES MMMs. Encouraging findings revealed that the incorporation of microporous ZIF-90 particles led to notable enhancements in hydrophobicity, alcohol affinity, and thermal stability of the MMMs. Notably, a distinctive cross-sectional morphology of the ZIF-90/PDMDES MMMs were observed at lower ZIF-90 loadings, a phenomenon attributed to the disparity between the ZIF-90 particle size and the inherent thickness of the PDMDES layer. Systematic evaluations were conducted to ascertain the influence of ZIF-90 loadings, feed concentration, and operational temperature on the pervaporation performance of ZIF-90/PDMDES MMMs. Accordingly, the optimal separation performance was obtained at the ZIF-90 loading of 5 wt% when separating ethanol from 5 wt% ethanol aqueous solution at 40 °C, yielding an impressive total flux of 6.51 kg∙m−2 h−1, a separation factor of 7.29, a PSI of 40.95 kg∙m−2 h−1, and an ethanol permeability of 7.45 × 104 Barrer.

Sustained free chlorine-releasing polydimethylsiloxane/Ca(ClO)2 materials with long-lasting disinfection efficacy.

A novel sustained chlorine-releasing polydimethylsiloxane/Ca(ClO)2 (PDMS/Ca(ClO)2) material was fabricated by encapsulating Ca(ClO)2 in a PDMS matrix due to its high hydrophobicity and high chemical stability, which showed immediate-responsive and long-lasting antibacterial capabilities in aqueous conditions. Free chlorine could be released from the PDMS/Ca(ClO)2 after immersion in water for 2 min and could also be sustainedly released for 2 weeks, while the released concentration is negatively related to the duration time and positively with the initial Ca(ClO)2 contents. Additionally, Ca(ClO)2 powder as a filler significantly affects the crosslinking and pore size of PDMS. The PDMS/Ca(ClO)2 materials exhibited enduring antibacterial performance against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) in both planktonic and multispecies-biofilm status. It is expected that this PDMS/Ca(ClO)2 material and its similar composite would be promising candidates for wide sustainable disinfection applications in biomedical and industrial fields.