Strong Hydrophobicity Research Articles

Stable Fabrication of Chitosan/Polycaprolactone (CS/PCL) Core-Shell Nanofibers by Electrospinning

Chitosan (CS), with its non-toxic and antibacterial properties, and Poly(ε-caprolactone) (PCL), known for its biodegradability and biocompatibility, are crucial materials in medical applications. This study proposed a solution utilizing electrospinning to manufacture fibers with nanometer-sized core-shell structures from these materials, with CS serving as the fiber core and PCL forming the shell. The influence of manufacturing technology parameters on fiber size and morphology was thoroughly researched and investigated. The solvent system used, Chloroform/Dimethylformamide (DMF), ensured complete solubility, viscosity control, conductivity, and proper solvent evaporation. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) results clearly demonstrated the morphology and internal structure of the nanofibers. The water contact angle (WCA) measurements of the fiber membrane showed almost no significant change over time, indicating strong hydrophobicity of the nanofibers. Additionally, the FTIR spectrum revealed distinct core-shell layers without any blending between them, while DSC analysis showed the thermal properties of fiber membranes. In summary, the electrospinning of nanofibers proved to be stable, producing thin fibers with an average diameter of approximately 400 nm. These findings are expected to significantly enhance the applicability of CS/PCL nanofibers across various fields, including healthcare and smart agriculture.

A novel approach for flotation separation of talc and molybdenite: Scrap steel-molybdenite galvanic corrosion treatment and its mechanism

Molybdenum is an important strategic resource. Talc-type molybdenite is abundant in reserves, but it is difficult to separate talc and molybdenite efficiently and cleanly because of their similar strong hydrophobicity. In this paper, the effect of galvanic corrosion between scrap steel and molybdenite on flotation behavior of molybdenite was studied under different conditions (different scrap steel materials, slurry water content, galvanic corrosion time and galvanic corrosion ambient temperature).The method for flotation separation of molybdenite and talc by galvanic corrosion of scrap steel-molybdenite was established for the first time. In addition, XPS, SEM, TOF-SIMS, contact Angle test and electrochemical test were used to study the effect of galvanic corrosion of scrap steel-molybdenite on the surface properties of molybdenite and talc. The results show that strong galvanic corrosion between scrap steel and molybdenite can significantly reduce the hydrophobicity of molybdenite, but there is no galvanic corrosion between scrap steel and talc under the same conditions, and scrap steel has no significant effect on the surface hydrophobicity of talc. Therefore, the galvanic corrosion of scrap steel-molybdenite can effectively expand the floatability difference between talc and molybdenite, and strengthen the flotation separation of molybdenite and talc. The flotation test results of artificial mixed ore show that in the case of mineral mixing, the galvanic corrosion of scrap steel-molybdenite still shows a strong inhibition effect on molybdenite flotation, so that 97.04 % of molybdenite in the mixed ore is inhibited into the tailings (molybdenite products). The research results expand the new high-value utilization way of scrap steel in sulfide ore flotation, and help to promote the sustainable development of iron and steel industry and sulfide ores industry. In addition, the research results also have reference significance for the use of scrap steel galvanic corrosion to inhibit other sulfide ores such as pyrite and arsenopyrite.

Anisotropic Wetting and Diffusion Behavior of Water Droplets on Biphenylene Compared to Graphene.

We comparatively studied the wetting behavior of water droplets on graphene and biphenylene using molecular dynamics simulations. The research showed that pristine biphenylene (BPN), unlike graphene, exhibits greater hydrophobicity and anisotropic wettability. This specific anisotropy can be tuned by the layer number and vacancy concentration. Particularly, there was a decrease in the water contact angle with increasing BPN layer number, highlighting the importance of water-BPN interactions. As the concentration of vacancies increases, the contact angle increases both along the zigzag direction and the armchair direction, while the anisotropy decreases. In planar defective biphenylene heterojunctions, water droplets spontaneously move from the defective area to the pristine area, where the zigzag direction exhibits a larger energy gradient compared to the armchair direction, leading to a faster movement of water droplets in the zigzag direction. The energy factor plays an important role in the directional movement of the water droplets. Our study explores new 2D materials with strong hydrophobicity and highlights the direction-dependent wetting behavior of biphenylene.

Insight into the effect of natural aging of polystyrene microplastics on the sorption of legacy and emerging per- and polyfluorinated alkyl substances in seawater

Microplastics (MPs) are abundant in aquatic environments and due to their small size, surface properties, and strong hydrophobicity, they can easily sorb chemicals, thus potentially acting as pollutant carriers. To date, most studies investigating the sorption of chemicals on MPs have principally focused on virgin MPs. However, MPs in the environment undergo aging effects, which changes their physical-chemical properties and aptitude to interact with chemicals, such as per- and polyfluorinated alkyl substances (PFAS) referred to as “forever chemicals”. In this study, we compared the sorption behavior of nine PFAS, exhibiting different physical-chemical properties, on virgin and naturally aged polystyrene microplastic (PS-MPs) to explore to what extent the environmental aging affects the sorption behavior of the PS-MPs for different legacy and emerging PFAS in seawater. Differences in the morphology and surface properties of aged PS-MPs were examined by infrared spectroscopy, surface area analysis, scanning electron microscopy, and X-ray diffraction. Results revealed that compared to virgin PS-MPs, aged PS-MPs exhibited morphological changes (e.g. cavities, pits, and rough surfaces) with biofilm development and signs of oxidation on the MPs surface. PFAS sorption on PS-MPs was enhanced for the aged PS-MPs compared to virgin PS-MPs with Kd values ranging from 327 L kg−1 for PFOA to 3247 L kg−1 for PFOS in aged PS-MPs. The difference in sorption capacity was mainly attributed to the physical-chemical changes and the adhered biofilm observed in aged PS-MPs. Results also showed that virgin PS-MPs adsorb PFAS mainly through steric hindrance, while the aged PS-MPs may involve more complex sorption mechanisms. This research provides additional insights into the ability of aged MPs as potential carriers of legacy and emerging contaminants in the marine environment.

Synergistically Activated Aggregation-Induced Emission Probe for Precise In Situ Staining of Lipids in Atherosclerotic Plaques.

Visualizing the localization and distribution of lipids within arteries is crucial for studying atherosclerosis. However, existing lipid-specific probes face challenges such as strong hydrophobicity and nonspecific staining of lipophilic organelles or tissues, making them impractical for the precise identification of atherosclerotic plaques. To address this issue, we design a synergistically activated probe, Cbz-Lys-Lys-TPEB, which responds to cathepsin B (CTB) and H2O2 for the in situ generation of aggregation-induced emission luminogens (AIEgens). This enables specific staining of lipids within arteries and precise imaging of atherosclerotic plaques. The probe combines a tetraphenylethene building block with a hydrophilic peptide sequence (Cbz-Lys-Lys) and phenylboric acid module, providing excellent water solubility and fluorescence quenching in a molecular dispersion state. Upon interaction with H2O2 and CTB within plaques, the hydrophilic Cbz-Lys-Lys-TPEB probe is specifically cleaved and converted into hydrophobic AIEgens, leading to rapid aggregation and significant fluorescence enhancement. Interestingly, the in situ-liberated AIEgens display distinct lipid binding ability, effectively tracking the location and distribution of lipids in plaques. This synergistic target-activated AIEgen liberation strategy demonstrates significant feasibility for the reliable and accurate identification of atherosclerotic plaques, holding tremendous potential for clinical diagnosis and risk stratification of atherosclerosis.

The adsorption and photocatalytic degradability of poly(lactic acid)/modified copper-based metal-organic frameworks meltblown fiber membranes on volatile organic compounds

In this work, a copper-based metal-organic framework (CuBTC) was synthesized by the solvent-thermal method, and then m@CuBTC was prepared to enhance its performance. Moreover, m@CuBTC was characterized by scanning electron microscopy, contact angle analysis, and thermogravimetric analysis, which exhibited m@CuBTC had strong hydrophobicity after surface modification. Furthermore, poly(lactic acid) (PLA) based nanocomposite fiber membranes were prepared by meltblown nonwoven technology with m@CuBTC as a functional additive. The structure characterization showed that m@CuBTC improved compatibility and dispersion within PLA, and excellent thermal stability. The PM2 nanocomposite fiber membranes (with a CuBTC addition of 0.3 wt%) demonstrated high porosity of 84.9 %, a specific surface area of 35.53 m²/g, and the crystallinity of 53.95 %, which also showed a maximum adsorption capacity for ethyl acetate of 266.93 mg/g according to the fitting results of Langmuir model. Furthermore, the PM2 membranes exhibited a high photocatalytic degradability, achieving a removal rate of 93.7 % for ethyl acetate, which only slightly decreased to 86.7 % after five reusability cycles. Consequently, the PLA-based nanocomposite fiber membranes present a promising solution for VOC treatment in industrial applications.

Application of hydrophobic catalyst in formaldehyde-ethylene condensation reaction.

Using hydrophobic aerogel (AGL) as the carrier, the catalyst supported p-toluene sulfonic acid (p-TSA) is synthesized, and the impact of the hydrophobicity of the catalyst on the formaldehyde-ethylene condensation reaction is investigated. Water contact angle, XRD, N2 adsorption/desorption, IR, and thermogravimetric analysis are used to characterize the catalyst. The outcomes demonstrate the ability of p-TSA to be loaded onto the carrier and the strong hydrophobicity of the catalyst when using AGL as the carrier. The elemental analysis results indicate that when AGL is employed as the carrier, the catalyst not only has more active sites than the SiO2-supported catalyst, but can also effectively limit the loss of active sites, reducing the loss rate from 25.82% to 15.03%. The findings demonstrate that 1,3-dioxane (1,3-DX) had a higher selectivity, rising from 16.2% to 33.3% when using AGL as the carrier. It is discovered that 1,3-propanediol (1,3-PDO) can be directly synthesized with a selectivity of up to 80.5% by employing acetic acid as a solvent in place of water.

Adipogenic Effects of Cresyl Diphenyl Phosphate (Triphenyl Phosphate Alternative) through Peroxisome Proliferator-Activated Receptor Gamma Pathway: A Comprehensive Study Integrating In Vitro, In Vivo, and In Silico from Molecule to Health Risk.

Cresyl diphenyl phosphate (CDP), a novel organophosphate ester (OPE), has been detected in various environmental and human samples. However, there is very limited knowledge regarding its toxicity, mechanisms of action, and potential health risks. Using new alternative methods (NAMs), across the molecular interactions, signaling pathways, cell functions, animal effects, and population risks, we investigated the potential adipogenic effects and associated risks of CDP and legacy OPE triphenyl phosphate (TPHP) by acting on peroxisome proliferator-activated receptor gamma (PPARγ). Among the 19 screened OPEs, CDP bound to PPARγ with the highest binding potency, followed by TPHP. CDP activated PPARγ through fitting into the binding pocket with strong hydrophobicity and hydrogen bond interactions; CDP exhibited higher potency compared to TPHP. In 3T3-L1 cells, CDP enhanced the PPARγ-mediated adipogenesis activity, exhibiting greater potency than TPHP. The intracellular concentration and receptor-bound concentrations (RBC) of CDP were also higher than those of TPHP in both HEK293 cells and 3T3-L1 cells. In mice, exposure to CDP activated the PPARγ-mediated adipogenic pathway, leading to an increased white adipose tissue weight gain. Overall, CDP could bind to and activate PPARγ, thereby promoting preadipocyte differentiation and the development of white adipose tissue. Its potential obesogenic risks should be of high concern.

Nanoconfinement effect on the miscible behaviors of CO2/shale oil/surfactant systems in nanopores: Implications for CO2 sequestration and enhanced oil recovery

Currently, CO2 flooding is the most promising carbon capture, utilization, and storage (CCUS) technology in the energy industry. Understanding the nanoconfinement effect on the CO2-oil miscible process is crucial for accurately determining the minimum miscibility pressure (MMP) of CO2/oil in shale reservoirs. In this study, we conducted molecular dynamics (MD) simulations to investigate the effects of pore size, surfactants, and pore type on the MMP of nanoconfined CO2/shale oil/surfactant systems. Validations against experimental data show a deviation of 2.98 % in the CO2 MMP. The MMPs under nanoconfinement are found to be significantly lower than those in bulk phase conditions (up to 22.94 %). The simulation results reveal that decreasing pore size can enhance the miscibility of CO2 and oil by increasing the CO2 adsorption ratio, improving CO2-surfactant interactions, and inhibiting the tendency of CO2 molecules to self-aggregate. The enhancement of CO2-oil miscibility caused by surfactants is ranked by CFP > SF > SDS according to the mixing degrees (Dmix) and the spatial distribution of CO2 around surfactant molecules. In addition, pore type exhibits various abilities in influencing the MMP, owing to their different mineral surface properties and ability to influence CO2-surfactant interactions. Nanopores with stronger hydrophobicity and a denser CO2 distribution around surfactant molecules have lower MMPs. The results show that the order of MMP in terms of pore types is Quartz < Kaolinite < I/M clay. This study elaborates the micro-mechanisms of surfactant-assisted CO2-oil miscibility under nanoconfinement, offering valuable insights for effectively designing CO2 miscible flooding in shale oil reservoir development.

Hydrophilicity Dependent Distribution of Water at Ionic Liquids/Metal Interface Monitored by Electrochemical SERS.

The understanding of the interfacial processes is critically important for extending the practical application of ionic liquids, particularly for the role of interfacial water. In the electrochemical system based on ionic liquid electrolytes, small amounts of water at the interface generate a significant change in the electrochemical behaviors of ionic liquids. Therefore, the investigation on the interfacial behavior of water is highly desired in ionic liquids with different anions, water content, and hydrophilicity. Herein, based on the probe strategy, in situ surface enhanced Raman spectroscopy (SERS) combined with electrochemical control (EC-SERS) was developed to investigate the influence of hydrophilicity/hydrophobicity of ionic liquids on the interfacial water. The water-sensitive transformation reaction of 4,4'-dimercaptoazobenzene (DMAB) to para-aminothiophenol (PATP) was employed as a probe reaction for investigating the behavior of interfacial water. The changes of relative SERS intensities of DMAB to PATP served as an indication of the quantity variation of interfacial water. The results show that the transformation reaction efficiencies were critically dependent on the additional water contents, potential, and hydrophilicity of ionic liquids. With a very low molar fraction of additional water (Xw = 0.01), transformation efficiency of DMAB (the amount of interfacial water) followed the sequence of [BMIm]BF4 < [BMIm]PF6 < [BMIm]Tf2N. It was in agreement with the hydrophobicity order of the ionic liquids. With the increase in additional water content, the potential for the full transformation was positively moved, and the efficiency increased significantly. The stronger hydrophobicity allowed more water molecules to migrate to the interface, which was attributed to the difference in interactions between water and the anions of ionic liquids. It demonstrated that the small amount of water tended to gather at the interface in hydrophobic ionic liquids. Compared to traditional cyclic voltammetry, the EC-SERS technique combined with probe reactions is more sensitive to interfacial water. It is anticipated to develop as a promising tool for the investigating water-related issues at interfaces and to provide guidance to screen ionic liquids for practical application.

Evaluation of probiotic efficacy of indigenous yeast strain, Saccharomyces cerevisiae Y-89 isolated from a traditional fermented beverage of West Bengal, India having protective effect against DSS-induced colitis in experimental mice.

Increasing awareness regarding health promotion and disease prevention has driven inclusion of fermented foods and beverages in the daily diet. These are the enormous sources of beneficial microbes, probiotics. This study aims to isolate yeast strains having probiotic potential and effectivity against colitis. Initially, ninety-two yeast strains were isolated from Haria, an ethnic fermented beverage of West Bengal, India. Primary screening was done by their acid (pH 4) and bile salt (0.3%) tolerance ability. Four potent isolates were selected and found effective against Entamoeba histolytica, as this human pathogen is responsible to cause colitis. They were identified as Saccharomyces cerevisiae. They showed luxurious growth even at 37 oC, tolerance up to 5% of NaCl, resistance to gastric juice and high bile salt (2.0%) and oro-gastrointestinal transit tolerance. They exhibited good auto-aggregation and co-aggregation ability and strong hydrophobicity. Finally, heat map and principal component analysis revealed that strain Y-89 was the best candidate. It was further characterised and found to have significant protective effects against DSS-induced colitis in experimental mice model. It includes improvement in colon length, body weight and organ indices; reduction in disease activity index; reduction in cholesterol, LDL, SGPT, SGOT, urea and creatinine levels; improvement in HDL, ALP, total protein and albumin levels; decrease in coliform count and restoration of tissue damage. This study demonstrates that the S. cerevisiae strain Y-89 possesses remarkable probiotic traits and can be used as a potential bio-therapeutic candidate for the prevention of colitis.

Fluorinated MIL-53(Al) with breathing effect incorporated mixed matrix membranes for enhanced butanol/water pervaporation performance

Fillers of mixed matrix membranes (MMMs) play a crucial role in the pervaporation (PV) separation process. MIL-53(Al) is widely used in the preparation of MMMs due to its high stability, variable pore size, and ease of modification. In this study, fluorinated MIL-53(Al) (4F-MIL-53) was successfully synthesized using a solvent-free method. The introduction of fluorinated group made 4F-MIL-53 have better affinity for butanol and stronger hydrophobicity than MIL-53. Meanwhile, by utilizing its breathing effect, 4F-MIL-53 with narrow pore (4F-MIL-53(np)) could be transformed to 4F-MIL-53 with large pore (4F-MIL-53(lp)) through heat treatment. Also, the flexible framework of 4F-MIL-53 had good affinity with polymer chains. Then, 4F-MIL-53(lp) was introduced into PEBA to prepare MMMs for separating n-butanol/water. Compared with pristine PEBA membrane, the permeation flux and separation factor of the 4F-MIL-53(lp)-20/PEBA MMMs increased by 100.5 % and 90.4 %, respectively. Theoretical calculations indicated that there were multiple intermolecular forces between 4F-MIL-53(lp) and n-butanol, which enhanced the mixed matrix membrane affinity for n-butanol. The calculated self-diffusion coefficient of water in 4F-MIL-53 (lp) was lower than that in MIL-53, indicating that the introduction of fluorinated groups enhanced the hydrophobicity of MMMs. The proposed selection and modification strategies of MOF fillers provide excellent guidance for getting MMMs with high performance.

Unlocking multi-photon excited luminescence in pyrazolate trinuclear gold clusters for dynamic cell imaging

The family of coinage-metal-based cyclic trinuclear complexes exhibits abundant photophysical properties, promising for diverse applications. However, their utility in biochemistry is often hindered by large particle size and strong hydrophobicity. Meanwhile, the investigation into multi-photon excited luminescence within this family remained undocumented, limiting their potential in bio-imaging. Herein, we unveil the multi-photon excited luminescent properties of pyrazolate-based trinuclear gold(I) clusters, facilitated by excimeric gold(I)···gold(I) interactions, revealing a nonlinear optical phenomenon within this family. Furthermore, to address issues of poor biocompatibility, we employ electrospinning coupled with hydroxypropyl-beta-cyclodextrin as the matrix to fabricate a flexible, durable, transparent, and red emissive film with a photoluminescence quantum yield as high as 88.3%. This strategy not only produces the film with sufficient hydrophilicity and stability, but also achieves the downsizing of trinuclear gold(I) clusters from microscale to nanoscale. Following the instantaneous dissolution of the film in the media, the released trinuclear gold(I) nanoparticles have illuminated cells and bacteria through a real-time, non-toxic, multi-photon bio-imaging approach. This achievement offers a fresh approach for utilizing coinage-metal-based cyclic trinuclear complexes in biochemical fields.

Effect of Surfactants on Eliminating Stable Ultrafine Chalcopyrite Froth.

Chalcopyrite is a primary source of copper in nature. However, with the increasing need to process low-grade and complex chalcopyrite ores, overly stable froth is becoming more and more common and poses operational and safety challenges. No reliable strategy has been developed to address the issue. As a new initiative, this study investigated three different structured surfactants, sodium dodecyl sulfate (SDS), sodium dodecylbenzenesulfonate (SDBS), and pentadecafluorooctanoic acid (PFOA), which vary in hydrophobic group, aiming to modify the surfaces of ultrafine chalcopyrite particles and adjust the interfacial tension at the gas-liquid interface to eliminate stable ultrafine chalcopyrite froth. The fundamental hypothesis was that an ideal surfactant structure could adjust the particle surface wettability and interfacial tension to eliminate overly stable froth. Based on contact angle measurements and interfacial tension measurements using a Theta Flow tensiometer by the pendant drop method and the sessile drop method, it was demonstrated that the contact angle played a dominant role in defoaming, while the reduction of gas-liquid interfacial tension had an adverse effect. Additionally, defoaming tests indicated that SDBS had lower defoaming effectiveness than SDS at low surfactant concentrations due to the steric hindrance in its structure, whereas the addition of SDBS could achieve a froth reduction efficiency as high as 93.75% at higher surfactant concentrations due to its stronger hydrophobicity and adsorption capacity to chalcopyrite particles, which could reduce the contact angle from 70 to 37.62°. However, PFOA exhibited lower defoaming effectiveness than both SDS and SDBS due to its lipophobic fluorocarbon tail of PFOA and weaker adsorption capacity to chalcopyrite particles, making it unsuitable for eliminating stable ultrafine chalcopyrite froth.

Impact of forest fire severity on soil physical and chemical properties in pine and scrub forests in high Andean zones of Peru

Forest fires are the main threat to ecosystems and human life. The frequency, seasonality, extent and severity of fires affect ecosystems and the physical and chemical properties of the soil by direct (heating) and indirect (ash) effects. This could affect biodiversity and forest residency in the face of climate change. In this study, we evaluated the impact of fire severity on soil physical and chemical properties caused by forest fires in a high Andean area of Peru. For this purpose, the severity levels, the degree of hydrophobicity, and the physical and chemical properties of the soil were analyzed by sampling in affected areas (Pinus radiata D. Don plantation and shrubland) and unaffected areas. The results showed a very low severity in soil components, with a strong hydrophobicity, more persistent in the forest plantation area than in the shrubland. The physical properties of the soil did not show variations; however, in the Pinus plantations they showed variations in their chemical properties such as pH, electrical conductivity, organic matter, nitrogen and cation exchange capacity compared to areas not affected by the forest fires. Likewise, in the study area an adequate regeneration process was evidenced; in fact, it is important to apply mechanisms to accelerate the restoration of the vegetation cover and the physical and chemical quality of the vegetation.

The Effect of Hydrophobic Modified Block Copolymers on Water-Oil Interfacial Properties and the Demulsification of Crude Oil Emulsions.

The demulsification effect of three types of block copolymers, BP123, BPF123, and H123, with the same PEO and PPO segments but different hydrophobic modification groups on crude oil emulsions and the properties of oil-water interfaces were investigated using demulsification experiments, an interfacial tensiometer, and surface viscoelastic and zeta potential instruments in this paper. The results showed that the hydrophobic modification group of the block copolymers had great effects on the demulsification performance. The H123 block copolymers with the strongest hydrophobicity had the best demulsification effect on the crude oil emulsions. The properties of the oil-water interfaces indicated that the modified block copolymers achieved the demulsification of crude oil emulsions by reducing the strength of the oil-water interfacial film and the interfacial tension.

In-situ deposition modification of hydrophilic polytetrafluoroethylene (PTFE) membranes using surfactants as anchoring points for long-term stability

Polytetrafluoroethylene (PTFE) membranes are renowned for their excellent thermal stability, resistance to strong acids and alkalis, and superior mechanical stability. However, its inherent strong hydrophobicity significantly limits its use in water treatment. In this study, a SiO2 coating was successfully deposited in-situ on the surface of PTFE membranes using a hydrolyzed solution of tetraethyl orthosilicate (TEOS) compounded with the commercial fluorinated polyoxyethylene ether surfactant FS-31 (C6F13CH2CH2O(CH2CH2O)nH). The modification mechanism involves using the low surface energy nonionic fluorocarbon surfactant FS-31, which interacts hydrophobically with the PTFE substrate, serving as an “anchor” point around which the TEOS hydrolyzes and condenses around the fibers and nodes of the PTFE membrane, forming a complete and stable chemical network structure. The results show that the initial water contact angle of the modified membrane dropped to 36.5°, and the water flux reached 537.9 L m−2 h−1. After being continuously immersed in strong acid (5 wt% HCl), strong alkali (4 wt% NaOH), and oxidizing agent (5 wt% NaClO) for one week, the membrane maintained excellent hydrophilicity and stability. This study proposes a mild and efficient modification method to prepare durable hydrophilic PTFE membranes, portending great potential for applications in harsh environments.

Effect of different chain-length fatty acids on the retrogradation properties of rice starch

In order to delay the retrogradation of rice starch, the effects of three different chain length fatty acids (lauric acid, myristic acid and palmitic acid) on rice starch were studied. The fatty acids with longer carbon chains had strong steric hindrance and hydrophobicity, which formed a more compact structure in the helical cavity of amylose, and significantly reduced degree of expansion, migration of water, short-range ordered structure, number of double helical structures and crystallinity. These structural changes endowed the rice starch-long chain fatty acid complexes with better gel viscosity, liquid fluidity and thermal stability than in the rice starch-short chain fatty acid complexes. The results showed that fatty acids with longer chain length inhibited the retrogradation of rice starch, most obviously when 5% palmitic acid was added. This study provides an important reference for the processing of rice starch-based foods.

Structure-dependent destructive adsorption of organophosphate flame retardants on lipid membranes

The widespread use of organophosphate flame retardants (OPFRs), a serious type of pervasive environmental contaminants, has led to a global concern regarding their diverse toxicities to living beings. Using a combination of experimental and theoretical approaches, we systematically studied the adsorption, accumulation, and influence of a series of OPFRs on the lipid membranes of bacteria and cells. Our results revealed that OPFRs can aggregate in lipid membranes, leading to the destruction of membrane integrity. During this process, the molecular structure of the OPFRs is a dominant factor that significantly influences the strength of their interaction with the lipid membrane, resulting in varying degrees of biotoxicity. Triphenyl phosphate (TPHP), owing to its large molecular size and strong hydrophobicity, causes severe membrane disruption through the formation of nanoclusters. The corresponding severe toxicity originates from the phase transitions of the lipid membranes. In contrast, smaller OPFRs such as triethyl phosphate (TEP) and tris(2-chloroethyl) phosphate (TCEP) have weaker hydrophobicity and induce minimal membrane disturbance and ineffective damage. In vivo, gavage of TPHP induced more severe barrier damage and inflammatory infiltration in mice than TEP or TCEP, confirming the higher toxicity of TPHP. Overall, our study elucidates the structure-dependent adsorption of OPFRs onto lipid membranes, highlighting their destructive interactions with membranes as the origin of OPFR toxicity.

Optimization of the polishing process by integrating experimental design and high-throughput screening

Complex bispecific antibody formats tend to form more product-related impurities than monoclonal antibodies. The primary constraints are yield and purity in the polishing stage. The purpose of this study was to enhance the understanding of the optimal working window for four mixed-mode resins and to reduce the burden of resin screening and parameter optimization during process development. This study optimized the loading and elution conditions of four different mixed-mode cationic resins to enhance the yield and purity by integrating Design of Experiments with High-Throughput Screening. It was observed that despite being weakly acidic mixed-mode cationic resins, these four resins exhibited significant differences in their adsorption and elution performances and varied tolerances to salt concentrations. Capto MMC demonstrated strong hydrophobicity, while the performance profiles of MX-Trp-650 M and Nuvia cPrime were similar, with Nuvia cPrime showing superior purification effects. Eshmuno CMX, by extending its side chain ligand, achieved higher binding efficiency and capacity. Through the optimization of salt concentrations or the application of dual-gradient elution strategies, the target protein with high yield (77 %) and purity over 99 % was successfully obtained. This research not only provides in-depth insights into the application of mixed-mode chromatography in the biopharmaceutical field but also offers practical optimization strategies for the industrial-scale purification of bispecific antibodies.