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BACKGROUND: Tigecycline is widely used to treat infections in intensive care units. Drugs often need to be delivered to critically ill patients feeding by parenteral nutrition (PN). Before two preparations are administered in the same infusion line, the safety of this combination should be established. The objective of this study was to determine the compatibility of tigecycline with selected multichamber bag PN (MCB-PN). METHODS: Tigecycline was diluted in 0.9% sodium chloride solution and 5% glucose solution to obtain two 0.5 mg/ml solutions. Then the solutions were combined with selected MCB-PN in appropriate proportions. The samples were visually assessed, and pH, osmolality, turbidity, particle size, and zeta potential were measured. These measurements were made immediately after combining the solutions and after 4 h of storage at 23°C ± 1°C. RESULTS: It was determined that the pH values of the mixtures after combining with tigecycline changed by ≤0.1 unit. An increase in zeta potential was recorded, excluding one combination of tigecycline with the mixture. For all samples tested, the particle size distribution was within the acceptable range immediately after combination and after 4 h of storage. The difference in osmolality did not exceed ±3%, whereas the zeta potential decreased for only one combination. The turbidity of none of the samples exceeded a critical value. CONCLUSION: The physical compatibility of the tigecycline with five MCB-PN was proved. They can therefore be administered to patients in one infusion line using the Y-site.

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This article investigates the activation of surface groups of poly(ethylene terephthalate) (PET) fibers in woven fabric by hydrolysis and their functionalization with chitosan. Two types of hydrolysis were performed-alkaline and enzymatic. The alkaline hydrolysis was performed in a more sustainable process at reduced temperature and time (80 °C, 10 min) with the addition of the cationic surfactant hexadecyltrimethylammonium chloride as an accelerator. The enzymatic hydrolysis was performed using Amano Lipase A from Aspergillus niger (2 g/L enzyme, 60 °C, 60 min, pH 9). The surface of the PET fabric was functionalized with the homogenized gel of biopolymer chitosan using a pad-dry-cure process. The durability of functionalization was tested after the first and tenth washing cycle of a modified industrial washing process according to ISO 15797:2017, in which the temperature was lowered from 75 °C to 50 °C, and ε-(phthalimido) peroxyhexanoic acid (PAP) was used as an environmentally friendly agent for chemical bleaching and disinfection. The influence of the above treatments was analyzed by weight loss, tensile properties, horizontal wicking, the FTIR-ATR technique, zeta potential measurement and SEM micrographs. The results indicate better hydrophilicity and effectiveness of both types of hydrolysis, but enzymatic hydrolysis is more environmentally friendly and favorable. In addition, alkaline hydrolysis led to a 20% reduction in tensile properties, while the action of the enzyme resulted in a change of only 2%. The presence of chitosan on polyester fibers after repeated washing was confirmed on both fabrics by zeta potential and SEM micrographs. However, functionalization with chitosan on the enzymatically bioactivated surface showed better durability after 10 washing cycles than the alkaline-hydrolyzed one. The antibacterial activity of such a bio-innovative modified PET fabric is kept after the first and tenth washing cycles. In addition, applied processes can be easily introduced to any textile factory.

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Streptococcus pneumoniae, a leading cause of corneal infections worldwide, are extremely aggressive despite antibiotic sensitivity and exhibit increased resistance towards antibiotics. Antimicrobial peptides are often considered as potent alternatives against antibiotic resistance and here we have investigated the possible roles of S100A12, a host defense peptide, in wound healing and S. pneumoniae infection. S100A12 significantly inhibited growth of S. pneumoniae by disruption of membrane integrity along with increased generation of reactive oxygen species. Additionally, S100A12 accelerated cell migration and wound closure in human corneal epithelial cells and in a murine corneal wound model by activation of EGFR and MAPK signaling pathways.

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Counterion adsorption at the solid-liquid interface affects numerous applications. However, the counterion adsorption density in the Stern layer has remained poorly evaluated. Here we report the direct determination of surface charge density at the shear plane between the Stern layer and the diffuse layer. By the Grahame equation extension and streaming current measurements for different solid surfaces in different aqueous electrolytes, we are able to obtain the counterion adsorption density in the Stern layer, which is mainly related to the surface charge density but is less affected by the bulk ion concentration. The charge inversion concentration is further found to be sensitive to the ion type and ion valence rather than to the charged surface, which is attributed to the ionic competitive adsorption and ion-ion correlations. Our findings offer a framework for understanding ion distribution in many physical and chemical processes where the Stern layer is ubiquitous.

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Curcumin (CUR) has received worldwide attention for its beneficial effects on human health. Research report possible cytotoxic activity against various cancers, including glioblastoma. So far, little attention has been given to the binding properties of CUR to lipid membranes, which influences their electrical characteristics and can provide insight into their membrane-permeation abilities. Biophysical interactions between the polyphenol and in vitro models (liposomes and LN-18 human glioblastoma cells) were investigated by monitoring zeta potential and the membrane's surface charge as a function of pH. We focused on practical measurements and undertook a theoretical analysis of interactions in the natural cell membrane. We used the MTT assay to evaluate the viability of CUR-treated cells. Measurements performed using the Electrophoretic Light Scattering method demonstrated the dose-dependent effect of CUR on both membrane surface charge and zeta potential analyzed in vitro models. We determined theoretical parameters characterizing the cell membrane based on a quantitative description of the adsorption equilibria formed due to the binding of solution ions to the membrane of glioblastoma cells. The interaction of CUR with liposomes and human cancer cells is pH-dependent.

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The aim of this study was to investigate the effect of varying concentrations of furcellaran (FUR) and safflower (Carthamus Tinctorius) oil on the functional properties of emulgels as potential carriers of bioactive substances. The textural, mechanical, thermal and structural properties of twenty different formulations were characterised. The pH stability and zeta-potential of the emulgels was also examined. It was found clear correlation between gelling agent and oil fraction content and investigated properties. The hardness, strength, thermal stability expressed as melting point of the investigated systems increased with increasing concentration of the furcellaran and decreasing proportion of safflower oil, which indicated a significant weakening of the structure as a result of the addition of the oil fraction. Stored under refrigeration, emulgels appeared to be relatively stable showing a slight decrease in pH values after 7 days. Swelling ratio (SW) of emulgels increased with increasing both, polysaccharide and oil content, in emulgels. Based on the microstructure analyses, it can also be concluded that only part of the added safflower oil chemically bound to the functional groups of the polysaccharide, while the vast majority of it was only physically immobilized in the furcellaran matrix. Colour of furcellaran - safflower oil emulsion gels depended largely on the amount of oil fraction. The presented research demonstrating the wide spectrum of functional properties of polysaccharide-oil systems is a first step to developing a carrier composition for lipophilic compounds at further stages of research.

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Thromboembolic complications still arise on blood contacting surfaces. Surface charge and topography influence the subsequent deposition of proteins and platelets, potentially leading to thrombi. Research showed a correlation of surface charge and nanoscale roughness, and a negative surface charge as well as a smooth surface finish are associated with lower thrombogenicity. The aim of this study was to compare the platelet adhesion on titanium with different nanoscale roughnesses and to examine if those roughness variations caused a change in surface charge. Titanium samples were polished and roughened to four different nanoscale roughness levels. Platelet adhesion (covered surface area (CSA), N = 8) was tested in flow chambers with human whole blood using fluorescence imaging. ζ-potential was measured over a broad range of pH-values and interpolated to obtain the ζ-potential for pHBlood (7.4). Platelet adhesion tests were evaluated in terms of p-values and the Wilcoxon test effect size and the trend of the ζ-potential at pHBlood and the CSA was compared. Ra-values ranged between 35 (polished) and 156 nm. Regarding platelet adhesion, the polished sample showed the lowest mean CSA with a medium or strong effect size compared to the roughened samples. The interpolated ζ-potentials for pHBlood follow a similar trend as the CSA, with the lowest ζ-potential measured for the polished surface. These findings suggest that the decreasing ζ-potential due to lower nanoscale roughness might be an additional explanation for the improved hemocompatibility besides the smoother topography.

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This study investigates the impact of cellulose-derived polymers, anionic carboxymethylcellulose (CMC), and cationic cellulose (CC) on the colloidal and thermal stability of zeolite Na-X materials. By exploring polymer adsorption onto Na-X surfaces and characterising the resultant materials, using FT-IR, XPS, SEM, PSD, CHN, and zeta potential, the research unveils how CMC and CC modify zeolite properties. This investigation elucidates the potential roles of these polymers in colloidal systems with zeolites, revealing their promise for crafting organic-inorganic materials. Additional insight was also provided by careful examination of the thermal stability (TGA-DSC) of the obtained cellulose/zeolite materials. Furthermore, the study distinguishes the different adsorption mechanisms of CMC and CC, with CMC relying on some weak interactions (H-bonding and van der Waals forces), while CC interacts mainly via electrostatic forces. Both CMC and CC can act as stabilizing agents, with CMC being more efficient and using both electrosteric and depletion stabilizations. Importantly, the concentration of CC plays a role in bridging flocculation, highlighting the concentration-dependent nature of the stabilization mechanism.

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The synergistic potential of using graphene oxide (GO) nanosheets and hydrolyzed polyacrylamide (HPAM) as GO enhanced polymer hybrid (GOeP) for enhancing oil recovery (EOR) purposes has drawn attention. However, the hybridization method and stability of GOeP have not been comprehensively studied. To cover this gap, the current study evaluates the stability of GOeP under different conditions, including temperatures such as 60 and 80 °C, high and low salinities, and the presence of Mg2+ ions (6430 and 643 ppm). Hence, GO nanosheets were synthesized and characterized through XRD, Raman, FTIR, and DLS techniques. The performance of five preparation methods was assessed to determine their ability to produce stable hybrids. Zeta potential and sedimentation methods, coupled with the ANOVA statistical technique, were used for measuring and interpreting stability for 21 days. Results revealed that the stability of GOeP in the presence of brine is influenced by hydrolyzation duration, the composition of the water used in polymer hydrolyzation, the form of additives (being powdery or in aqueous solution), and the dispersion quality, including whether the GO solution was prediluted. The results revealed that the positive impact of higher temperatures on the long-term stability of GOeP is approximately seven times less significant than the reduction in stability caused by salinity. Under elevated salinity conditions, a higher Mg2+ concentration led to an 80% decrease in long-term stability, whereas the temperature impact was negligible. These findings highlight the potential of GOeP for EOR applications, offering insights into optimizing stability under challenging reservoir conditions.

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A high protein walnut flour (HPWF) was obtained by defatting walnut flour (WF), which is a by-product of the oil industry. The objective of this study was the chemical and techno-functional characterization of HPWF. Composition, amino acid content, protein secondary structure, protein solubility and thermal transitions were measured. Besides, the techno-functional properties, emulsion activity and stability, and water holding and oil absorption capacities, of HPWF were evaluated. Also, the molecular mass of proteins under denaturing conditions and the microstructure of HPWF were evaluated by electrophoresis and confocal scanning laser microscopy, respectively. HPWF had 55.4% protein content and 21.5% total dietary fibre. In terms of HPWF amino acid composition, the limiting amino acids were the sulphurated cysteine and methionine. By FTIR analysis, the main secondary structures were ß-sheet (49%) followed by α-helix (24%); both structures are considered to be ordered. Likewise, HPWF soluble proteins increased at basic pH and HPWF proteins were separated in 11 bands with molecular masses ranging from 97 kDa to 18 kDa by electrophoresis. With respect to techno-functional properties, HPWF presented good emulsion activity (51%) and high thermal emulsion stability (46%). In addition, HPWF retained 571% and 242% of water and oil by weight, respectively. Finally, the micrograph showed the predominance of protein structures and fibre fragments, and the presence of few lipids mostly trapped. These results showed that HPWF is an interesting source of plant-based proteins and walnut flour can be used to obtain high protein ingredients from non-traditional sources.

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Bacterial membrane vesicles (BMVs) are extracellular vesicles secreted by either Gram-positive or Gram-negative bacteria. These BMVs typically possess a diameter between 20 and 250 nm. Due to their size, when these BMVs are suspended in another medium, they could be constituents of a colloidal system. It has been hypothesized that investigating BMVs as colloidal particles could help characterize BMV interactions with other environmentally relevant surfaces. Developing a more thorough understanding of BMV interactions with other surfaces would be critical for developing predictive models of their environmental fate. However, this bio-colloidal perspective has been largely overlooked for BMVs, despite the wealth of methods and expertise available to characterize colloidal particles. A particular strength of taking a more colloid-centric approach to BMV characterization is the potential to quantify a particle's attachment efficiency (α). These values describe the likelihood of attachment during particle-particle or particle-surface interactions, especially those interactions which are governed by physicochemical interactions (such as those described by DLVO and xDLVO theory). Elucidating the influence of physical and electrochemical properties on these attachment efficiency values could give insights into the primary factors driving interactions between BMVs and other surfaces. This chapter details methods for the characterization of BMVs as colloids, beginning with size and surface charge (i.e., electrophoretic mobility/zeta potential) measurements. Afterward, this chapter will address experimental design, especially column experiments, targeted for BMV investigation and the determination of α values.

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Legumes are abundant sources of proteins, and white common bean proteins play an important role in air-water interface properties. This study aims to investigate the technical-functional properties of white common bean protein isolate (BPI) as a function of pH, protein concentration, and guar gum (GG) presence. BPI physicochemical properties were analyzed in terms of solubility, zeta potential, and mean particle diameter at pH ranging from 2 to 9, in addition to water-holding capacity (WHC), oil-holding capacity (OHC), and thermogravimetric analysis. Protein dispersions were evaluated in terms of dynamic, interfacial, and foam-forming properties. BPI showed higher solubility (>80 %) at pH 2 and above 7. Zeta potential and mean diameter ranged from 15.43 to -34.08 mV and from 129.55 to 139.90 nm, respectively. BPI exhibited WHC and OHC of 1.37 and 4.97 g/g, respectively. Thermograms indicated decomposition temperature (295.81 °C) and mass loss (64.73 %). Flow curves indicated pseudoplastic behavior, with higher η100 values observed in treatments containing guar gum. The behavior was predominantly viscous (tg δ > 1) at lower frequencies, at all pH levels, shifting to predominantly elastic at higher frequencies. Equilibrium surface tension (γeq) ranged from 43.87 to 41.95 mN.m-1 and did not decrease with increasing protein concentration under all pH conditions. All treatments exhibited ϕ < 15°, indicating predominantly elastic surface films. Foaming properties were influenced by higher protein concentration and guar gum addition, and the potential formation of protein-polysaccharide complexes favored the kinetic stability of the system.

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Sperm morphology significantly influences the fertilization capacity of male germ cells. Morphological abnormalities are frequently associated with an overproduction of reactive oxygen species (ROS), leading to further sperm damage and subsequent infertility. This case study examines a couple facing infertility, with male factor infertility identified as the primary issue, characterized by teratozoospermia and a high DNA fragmentation index (DFI). The objective was to assess the efficacy of zeta potential (ZP) as a sperm sorting technique for intracytoplasmic sperm injection (ICSI) in patients showing high DNA fragmentation. A 34-year-old male with abnormal sperm parameters underwent ICSI using the ZP technique for sperm separation, while his 28-year-old female partner received ovarian stimulation. This intervention resulted in the development of two good-quality blastocysts, resulting in a successful embryo transfer (ET) and a positive pregnancy outcome. Previous attempts using conventional assisted reproductive technologies (ART), including in vitro fertilization (IVF), followed by ICSI and ET, as well as other sperm selection methods, were not successful. The ZP-based approach demonstrated significant benefits by selecting spermatozoa with optimal parameters, such as negative membrane potential, thereby enhancing the success rate. This case emphasizes the advantages of personalized treatment strategies in managing male infertility and highlights the potential of advanced sperm sorting techniques in improving fertility outcomes.

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The increasing utilization of zinc oxide nanoparticles (ZnO-NPs) in many consumer products is of concern due to their eventual release into the natural environment and induction of potentially adverse impacts. The behaviour and environmental impacts of ZnO-NPs could be altered through their interactions with environmentally coexisting substances. This study investigated the changes in the behaviour of ZnO-NPs in the presence of coexisting organic pollutants (such as perfluorooctanoic acid [PFOA]), natural organic substances (i.e., humic acid [HA]), and electrolytes (i.e., NaCl and CaCl2) in simulated waters. The size, shape, purity, crystallinity, and surface charge of the ZnO-NPs in simulated water after different interaction intervals (such as 1 day, 1 week, 2 weeks, and 3 weeks) at a controlled pH of 7 were examined using various characterization techniques. The results indicated alterations in the size (such as 162.4 nm, 1 day interaction to >10 µm, 3 weeks interaction) and zeta potential (such as -47.2 mV, 1 day interaction to -0.2 mV, 3 weeks interaction) of the ZnO-NPs alone and when PFOA, electrolytes, and HA were present in the suspension. Different influences on the size and surface charge of the nanoparticles were observed for fixed concentrations (5 mM) of the different electrolytes. The presence of HA-dispersed ZnO-NPs affected the zeta potential. Such dispersal effects were also observed in the presence of both PFOA and salts due to their large aliphatic carbon content and complex structure. Cation bridging effects, hydrophobic interactions, hydrogen bonding, electrostatic interactions, and van der Waals forces could be potential interaction forces responsible for the adsorption of PFOA. The presence of organic pollutants (PFOA) and natural organic substances (HA) can transform the surface characteristics and fate of ZnO-NPs in natural and sea waters.

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High demand for rare earth elements (REEs) has increased interest in their recovery from unconventional sources, such as acid mine drainage (AMD). AMD contains elevated concentrations of Mn, Fe, and Al, which precipitate as (oxy)hydroxide minerals as pH is raised. These precipitates can remove cations including REEs and Co from solution via sorption and/or coprecipitation. In this study we developed a method to recover these critical minerals by sorption to MnO2, precipitated by oxidation of in situ Mn (II) with added KMnO4 at acidic pH. MnO2 solids were prepared with varying concentrations of KMnO4, SO42-, and Cl-, to elucidate the effects of excess KMnO4, SO42- concentration, and ionic strength on adsorption. When using a stoichiometric ratio of Mn (II) and KMnO4, 100% removal of REEs and Co occurred at approximately pH 3.5, nearly 2 pH units lower than was observed by sorption to Fe and Al hydroxysulfates. When using excess KMnO4 nearly 100% removal of REEs and Co was accomplished at approximately pH 2, although SO42- was found to inhibit REE sorption. From these results, we developed a two-stage process for recovery of REEs from AMD; a preliminary pH adjustment to remove Fe and Al hydroxy-sulfates, followed by adding KMnO4, precipitating MnO2, enabling recovery of REEs and Co. We tested this process in a representative synthetic AMD, achieving a grade of 6.16 mg REEs per g of solid, which is 65 % of the maximum possible grade based on solution composition. Fractionation of REEs was observed, with light REEs (LREEs) preferentially sorbed to MnO2 relative to both medium REEs (MREEs) and heavy REEs (HREEs). In contrast, preferential sorption of HREEs was observed for sorption to Fe and Al oxyhydroxides at all pH ranges. These results suggest the mechanisms of REE sorption differ among the solids and warrant further study.

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The toxicity of silver nanoparticles (AgNPs) depends on their physicochemical properties. The ongoing research aims to develop effective methods for modifying AgNPs using molecules that enable control over the processes induced by nanoparticles in both normal and cancerous cells. Application of amino acid-stabilized nanoparticles appears promising, exhibiting tunable electrokinetic properties. Therefore, this study focused on determining the influence of the surface charge of cysteine (CYS)-stabilized AgNPs on their toxicity towards human normal B (COLO-720L) and T (HUT-78) lymphocyte cell lines. CYS-AgNPs were synthesized via the chemical reduction. Transmission electron microcopy (TEM) imaging revealed that they exhibited a quasi-spherical shape with an average size of 18 ± 3 nm. CYS-AgNPs remained stable under mild acidic (pH 4.0) and alkaline (7.4 and 9.0) conditions, with an isoelectric point observed at pH 5.1. Following a 24 h treatment of lymphocytes with CYS-AgNPs, concentration-dependent alterations in cell morphology were observed. Positively charged CYS-AgNPs notably decreased lymphocyte viability. Furthermore, they exhibited grater genotoxicity and more pronounced disruption of biological membranes compared to negatively charged CYZ-AgNPs. Despite both types of AgNPs interacting similarly with fetal bovine serum (FBS) and showing comparable profiles of silver ion release, the biological assays consistently revealed that the positively charged CYS-AgNPs exerted stronger effects at all investigated cellular levels. Although both types of CYS-AgNPs have the same chemical structure in their stabilizing layers, the pH-induced alterations in their surface charge significantly affect their biological activity.

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Bile acids (BAs) are the main endogenous modulators of the composition and metabolic activity of the intestinal microbiota. In the present work, the effect of conjugated (glycodeoxycholic, glycocholic, taurodeoxycholic, taurocholic acids) and free BAs [cholic acid (CA) and deoxycholic acid (DCA)] on the survival, biological molecules, and structural and surface properties of two potential probiotic lactic acid bacteria (LAB) was evaluated. For this, viability assays, Raman spectroscopy, scanning electron microscopy (SEM), and zeta potential (ZP) measurements were employed. Our results evidenced that free BAs were more toxic than conjugates, with CA being significantly more harmful than deoxycholic acid (DCA). RAMAN studies show that BAs modify the bands corresponding to proteins, lipids, carbohydrates, and DNA. SEM showed that BAs cause surface distortions with depressions and fold formation, as well as incomplete cell division. DCA was the one that least altered the ZP of bacteria when compared to CA and taurodeoxycholic acid, with gradual changes towards more positive values. In general, the magnitude of these effects was different according to the BA and its concentration, being more evident in the presence of CA, even at low concentrations, which would explain its greater inhibitory effect. This work provides solid evidence on the effects of BAs on LAB that will allow for the development of strategies by which to modulate the composition of the microbiota positively.

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In this study, a new polyionic polymer inhibitor, TIL-NH2, was developed to address the instability of shale gas horizontal wells caused by water-based drilling fluids. The structural characteristics and inhibition effects of TIL-NH2 on mud shale were comprehensively analyzed using infrared spectroscopy, NMR spectroscopy, contact angle measurements, particle size distribution, zeta potential, X-ray diffraction, thermogravimetric analysis, and scanning electron microscopy. The results demonstrated that TIL-NH2 significantly enhances the thermal stability of shale, with a decomposition temperature exceeding 300 °C, indicating excellent high-temperature resistance. At a concentration of 0.9%, TIL-NH2 increased the median particle size of shale powder from 5.2871 µm to over 320 µm, effectively inhibiting hydration expansion and dispersion. The zeta potential measurements showed a reduction in the absolute value of illite's zeta potential from -38.2 mV to 22.1 mV at 0.6% concentration, highlighting a significant decrease in surface charge density. Infrared spectroscopy and X-ray diffraction confirmed the formation of a close adsorption layer between TIL-NH2 and the illite surface through electrostatic and hydrogen bonding, which reduced the weakly bound water content to 0.0951% and maintained layer spacing of 1.032 nm and 1.354 nm in dry and wet states, respectively. Thermogravimetric analysis indicated a marked reduction in heat loss, particularly in the strongly bound water content. Scanning electron microscopy revealed that shale powder treated with TIL-NH2 exhibited an irregular bulk shape with strong inter-particle bonding and low hydration degree. These findings suggest that TIL-NH2 effectively inhibits hydration swelling and dispersion of shale through the synergistic effects of cationic imidazole rings and primary amine groups, offering excellent temperature and salt resistance. This provides a technical foundation for the low-cost and efficient extraction of shale gas in horizontal wells.

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This study examined the influence of nanomaterials (NMs) on the organization of membrane lipids and the resulting morphological changes. The cell plasma membrane is heterogeneous, featuring specialized lipid domains in the liquid-ordered (Lo) phase surrounded by regions in the liquid-disordered (Ld) phase. We utilized model membranes composed of various lipids and lipid mixtures in different phase states to investigate the interactions between the NMs and membrane lipids. Specifically, we explored the interactions of pure chitosan (CS) and CS-modified nanocomposites (NCs) with ZnO, CuO, and SiO2 with four lipid mixtures: egg-phosphatidylcholine (EggPC), egg-sphingomyelin/cholesterol (EggSM/Chol), EggPC/Chol, and EggPC/EggSM/Chol, which represent the coexistence of Ld, Lo, and Ld/Lo, respectively. The data show that CS NMs increase the membrane lipid order at glycerol level probed by Laurdan spectroscopy. Additionally, the interaction of CS-based NMs with membranes leads to an increase in bending elasticity modulus, zeta potential, and vesicle size. The lipid order changes are most significant in the highly fluid Ld phase, followed by the Lo/Ld coexistence phase, and are less pronounced in the tightly packed Lo phase. CS NMs induced egg PC vesicle adhesion, fusion, and shrinking. In heterogeneous Lo/Ld membranes, inward invaginations and vesicle shrinking via the Ld phase were observed. These findings highlight mechanisms involved in CS NM-lipid interactions in membranes that mimic plasma membrane heterogeneity.

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In this study, the adsorption characteristics of novel activated biocarbons prepared from horsetail herb (a popular and troublesome weed) by physical activation (using carbon dioxide) and chemical one (using phosphoric(V) acid) in the process of simultaneous proteins immobilization in multicomponent solutions were examined. The carbon materials were characterized in terms of their porous structure, acidic-basic properties, and surface morphology. The binding mechanisms of such proteins as bovine serum albumin (BSA) and lysozyme (LSZ), differing in internal stability, were determined alone and in their blends. This was done based on the comprehensive analysis of the results of adsorption/desorption, surface, electrokinetic and stability measurements. These experiments were carried out over a wide pH range of 3-11. They included the following issues: (1) determination of the protein adsorbed/desorbed amounts on/from a surface of activated biocarbons; (2) study of the kinetics of these processes; (3) examination of the macromolecules impact on the surface charge density and zeta potential of the carbon materials; and (4) determination of the suspension stability and size of aggregates formed in the examined systems. The analysis of the obtained results indicated the differences in the binding mechanism of both proteins that is of key importance for their simultaneous immobilization on activated biocarbons surface in the soil environment.