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Natural polysaccharides can serve as carriers of genes owing to their intrinsic biocompatibility, biodegradability, and low toxicity. Additionally, they can be easily chemically modified, e.g., through grafting, leading to hybrid synthetic–biological copolymers with additional functionalities. In this work we report on the electrostatic interaction between a chitosan-g-poly(N-isopropylacrylamide) (Chit-g-PNIPAM) copolymer and DNA macromolecules of different lengths (i.e., 50 and 2000 bp), towards the construction of polyplexes that can serve as potential gene delivery systems. At the basic science level, the work aims to elucidate the effects of DNA length on the structural and physicochemical properties of the thermoresponsive hybrid macromolecular assemblies. The protonated amino groups on the chitosan backbone enable electrostatic binding with the anionic phosphate groups of the DNA molecules, while the PNIPAM side chains are expected to impart thermoresponsive properties to the formed polyplexes. Different amino to phosphate group (N/P) mixing ratios were examined, aiming to produce stable dispersions. The physicochemical properties of the resulting polyplexes were investigated by dynamic and electrophoretic light scattering (DLS and ELS), while their morphology was studied by scanning-transmission electron microscopy (STEM). Moreover, their response to changes in temperature and ionic strength, as well as their stability against biological media, was also examined. Finally, the binding affinity of the copolymer towards DNA was evaluated through fluorescence spectroscopy, using ethidium bromide quenching assays, while infrared spectroscopy was used to investigate the structure of the incorporated DNA chains. [ABSTRACT FROM AUTHOR]

A reversible associated copolymer capable of healing at room temperature was constructed using acrylic acid (AA) and hemin as anionic monomers, and methacryloyloxyethyl trimethylammonium chloride (DMC) as the cationic monomer. Through optimization of the synthesis conditions, characterization by 1HNMR, infrared spectroscopy, ultraviolet-visible spectroscopy, Thermogravimetric analysis, differential scanning calorimetry, and construction of reasonable models for dynamic simulation, the following conclusions were obtained: The introduction of Hemin could convert light energy into heat energy, accelerating the healing of damaged areas; the predicted glass transition temperature value matched well with the experimental value, demonstrating the reliability of the constructed polymer model; the cohesive energy density (CED), dominated by electrostatic interactions, was identified as the key factor in the self-healing mechanism; the study also visually captured the microscopic process of self-healing within the polymer, providing a detailed understanding of the molecular rearrangements that facilitate this process. This work offers valuable insights into the design of reversible associated polymers, contributing to the broader goal of developing functional polymer materials aligned with circular economy principles. [ABSTRACT FROM AUTHOR]

Diatomic catalysts (DACs), as a frontier of research on atomically dispersed catalysts, have drawn great attention, especially in electrocatalysis. However, most of the current synthetic strategies for DACs suffer from poor efficiency and high cost. In this work, a novel noncovalent assembly strategy is reported for the efficient synthesis of DACs. By the aid of two kinds of noncovalent intermolecular force, the π–π stacking and Coulomb forces, a pair of metal complex ions with opposite electrical charges is spontaneously loaded onto the carbon substrate and transformed into diatomic sites via thermal treatment. This noncovalent assembly approach shows universal feasibility for a broad spectrum of DACs (Ir–Fe, Pt–Fe, Pt–Co, and Pt–Ni). To prove the practical utility, the as‐prepared PtFe‐DAC is deployed as oxygen reduction reaction catalyst, performing excellent activity with a half‐wave potential of 0.935 V (vs RHE) and a 2.3 times higher turnover frequency than that of the single‐atomic Fe‐SAC. In situ characterization and theoretical calculation indicate that the adjacent Pt sites could endow moderate activation of oxygen molecule on Fe sites by lowering the electron pairing energy as well as the modulation of the d‐band center and spin states of Fe centers propelling the desorption of the intermediates. [ABSTRACT FROM AUTHOR]

Chemical systems displaying directional motions are relevant to the operation of artificial molecular machines. Herein we present the functioning of a molecule capable of transporting a cyclic species in a preferential direction. Our system is based on a linear, non‐symmetric, positively charged molecule. This cation integrates into its structure two different reactive regions. On one side features a bulky ester group that can be exchanged by a smaller substituent; the other extreme contains an acid/base responsive moiety that plays a dual role, as part of the recognition motif and as a terminal group. In the acidic state, a dibenzo‐24‐crown‐8 ether slides into the linear component attracted by the positively charged recognition site. It does this selectively through the extreme that contains the azepanium group, since the other side is sterically hindered. After base addition, intermolecular interactions are lost; however, the macrocycle is unable to escape from the linear component since the energy barrier to slide over the neutral azepane is too large. Therefore, a metastable mechanically interlocked molecule is formed. A second reaction, now on the ester functionality, exchanges the bulky mesityl for a methyl group, small enough to allow macrocycle dissociation, completing the directional transit of the ring along the track. [ABSTRACT FROM AUTHOR]

Despite the extensive research on room temperature phosphorescent (RTP) materials, it remains a great challenge to further improve the photophysical properties of RTP materials. In this study, the RTP emission of guest molecule is significantly enhanced by constructing binary matrices containing cyanuric acid (CA) and amino‐containing compounds. Systematic studies show that the strong interaction between the two components of binary matrix induced variations in the guest molecular configuration and excited state electron distribution, thus facilitating the production of more triplet excitons. Furthermore, the binary matrix also exhibits stronger domain‐limiting effect compared to the CA mono‐matrix, effectively inhibits the energy loss of triplet excitons due to quenching and non‐radiative transitions. The prepared binary matrix RTP materials present ultralong phosphorescence lifetime and high phosphorescence quantum yield (up to 3.21 s and 7.31%, respectively), and even achieve bright RTP emission in a variety of organic solvents and aqueous media. Moreover, the RTP emission intensity of the best binary matrix composite can reach more than 28 times that of the CA mono‐matrix composite, and the RTP lifetime can be extended by 1.51 s. [ABSTRACT FROM AUTHOR]

Solution‐processable conducting polymers open up a new era in organic electronics, fundamentally altering the processing methods of electronic devices. P‐type conducting polymers, exemplified by aqueous solution‐processed poly(3,4‐ethylenedioxythiophene) : poly(styrenesulfonate) (PEDOT : PSS), have been successfully commercialized. However, the performance of electron‐transporting (n‐type) materials remains considerably poorer. One of the primary challenges lies in striking a balance between conductivity and solvent processability. At present, most n‐type conducting polymers necessitate toxic solvents for processing, which contradicts environmentally sustainable principles and impedes their potential for large‐scale industrial applications. Herein, we developed an alcohol‐processable high‐performance n‐type conducting polymer, poly(3,7‐dihydrobenzo[1,2‐b : 4,5‐b’]difuran‐2,6‐dione): poly(2‐ethyl‐2‐oxazoline) (PBFDO : PEOx), which utilized electrostatic interactions between PEOx and PBFDO to simultaneously achieve high conductivity and alcohol‐processability. The PBFDO : PEOx films exhibited remarkable electrical conductivity exceeding 1000 S cm−1 with outstanding stability even at temperatures up to 250 °C, establishing it as a prominent green solvent‐processed n‐type conducting polymer that rivals the most advanced p‐type counterparts. Various applications including organic thermoelectric, electrochemical transistor, and electrochromic devices were showcased, highlighting the broad potential of PBFDO : PEOx in advancing green organic electronics. [ABSTRACT FROM AUTHOR]

In the critical domain of wastewater treatment, the development of cost-effective, durable, and recyclable adsorbents with high adsorption capacities remains a significant challenge. This study introduces a novel magnetic bimetallic Metal–Organic Framework (MOF) adsorbent, MZIF-67-Co/Cu, doped with copper ions. The MZIF-67-Co/Cu adsorbent was successfully synthesized and structurally characterized, demonstrating remarkable selectivity for removing methyl orange (MO) from water. This high selectivity is attributed to the adsorbent's high porosity and Lewis base properties at the coordinating metal ion center. The incorporation of Cu ions significantly enhances the porous architecture and increases the number of metal adsorption sites, leading to an impressive maximum MO adsorption capacity of 39.02 mg/g under optimized conditions (0.5 g/L adsorbent concentration, pH 3.0, 250 rpm agitation speed, adsorption time > 10 min). The adsorption kinetics closely follow the pseudo-second-order model, and the isotherm data fit well with the Langmuir model. The primary adsorption mechanisms involve electrostatic attraction and mesoporous interaction. This study highlights MZIF-67-Co/Cu as a highly efficient adsorbent with magnetic recovery capabilities, positioning it as a promising candidate for addressing critical issues in wastewater treatment. [ABSTRACT FROM AUTHOR]

The rewritable wearables based on photochromism have emerged as attractive candidates in inkless printing applications. Among various photochromic materials, polyoxometalates have great potential for rewritable wearables, with major advantages in fast response upon UV irradiation, long‐term photochemical stability, and excellent fatigue resistance. However, the development of rewritable wearables based on polyoxometalates is limited by low combining fastness, weak stability, and poor scalability. Here, a scalable strategy is reported to fabricate an ideal rewritable wearable based on fundamental charge balance mechanism. The pristine cotton substrate is grafted by cationic polymer brushes to incorporate photochromic phosphomolybdic acid (PMoA) anions through electrostatic attraction, and then the cationic surfactants with alkyl chains are introduced to encapsulate the PMoA anions to achieve charge balance subsequently. The resultant rewritable wearables display the long‐awaited properties, such as high color contrast, favorable reversibility (>10 cycles), long color retention (>15 days) and high stability against detergent and sweat (pH 6.5–8.0) during repeated washing (50 cycles) and wearing. As a demonstration, a rewritable T‐shirt is scalably fabricated, and excellent antibacterial activity and biocompatibility are demonstrated as well, which is expected to be a sustainable solution for regular fabric printing in household products and public display. [ABSTRACT FROM AUTHOR]

Variable stiffness materials have shown considerable application in soft robotics. However, previously reported materials often struggle to reconcile high stiffness, stretchability, toughness, and self‐healing ability, because of the inherently conflicting requisite of these properties in molecular design. Herein, we propose a novel strategy that involves incorporating acid‐base ionic pairs capable of from strong crosslinking sites into a dense and robust hydrogen‐bonding network to construct rigid self‐healing polymers with tunable stiffness and excellent toughness. To demonstrate these distinct features, the polymer was employed to serve as the strain‐regulation layers within a fiber‐reinforced pneumatic actuator (FPA). The exceptional synergy between the configuration versatility of FPA and the dynamic molecular behavior of the supramolecular polymers equips the actuator with simultaneous improvement in motion dexterity, multimodality, loading capacity, robustness, and durability. Additionally, the concept of integrating high dexterity at both macro‐ and micro‐scale is prospective to inspire the design of intelligent yet robust devices across various domains. [ABSTRACT FROM AUTHOR]

Reprogrammable shape morphing is ubiquitous in living beings and highly crucial for them to move in normal situations, even to survive under dangerous conditions. There is increasing interest in using asymmetric hydrogel structures to understand and mimic living beings’ shape morphing upon an external trigger in a controlled way. However, these asymmetric or heterogeneous configurations cannot be further modified once the polymer hydrogels are prepared. Therefore, it is a great challenge to achieve reprogrammable shape morphing using the existing hydrogels. Inspired by marine amoebae, which transform into several different morphologies according to the various external salt concentrations, a new strategy is developed for salting hydrogels to reconfigure their anisotropy toward reprogrammable shape morphing. Polyampholyte hydrogels with equal stoichiometric COO− and N+(CH3)3 groups were first swollen in HCl/NaCl solution. After being then transferred into water, they first swollen again by water uptake driven by the osmotic pressure, and then were spontaneously deswollen due to increase in internal pH and dialysis of ions leading to deprotonation of COOH to COO− and regeneration of COO−/N+(CH3)3 electrostatic attraction. This work provides a novel strategy to reconfigure anisotropy of hydrogel soft actuators and to open up an avenue for reprogrammable shape morphing. [ABSTRACT FROM AUTHOR]

The World Health Organization (WHO) announced corona virus disease 2019 (COVID-19) caused by severe acute respiratory syndrome corona virus 2 (SARS-CoV-2), a serious pandemic in March 2020. The situation demands, development of rapid, convenient and easy to handle detection system for SARS-CoV-2. In this regard, the optical biosensing assay was developed using antisense oligonucleotide (ASO) conjugated Poly-l-Lysine functionalized gold nanoparticles (PLL-AuNPs) for detection of SARS-CoV-2 RNA. The negatively charged ASOs were conjugated with positively charged PLL-AuNPs by electrostatic interactions which were characterized by UV–Vis spectroscopy and Transmission Electron Microscopy (TEM). ASO-PLL-AuNPs conjugate was used to detect target SARS-CoV-2 RNA within 5–6 min from COVID-19 positive samples. In presence of target SARS-CoV-2 RNA, the DNA-RNA (ASO-RNA) hybrid structure was formed that released PLL-AuNPs which was aggregated in presence of sodium chloride (NaCl). This has rendered observable red shift in Surface Plasmon Resonance (SPR) with maximum absorbance at 660 nm and visual aggregation of PLL-AuNPs. Selectivity of ASO-PLL-AuNPs conjugate was evaluated in presence of Influenza A RNA with limit of detection 0.52 ng/µL. The obtained results were compared with qRT-PCR results for nasopharyngeal samples collected from COVID-19 positive patients and were found in good agreement with qRT-PCR results. This study reports selective and sensitive optical biosensing assay for detection of SARS-CoV-2 RNA using ASO-PLL-AuNPs conjugate without utilization of any sophisticated instruments. [ABSTRACT FROM AUTHOR]

The construction of flexible freestanding silicon‐based electrodes eliminates the addition of inactive materials, improving the overall energy density, and effectively avoiding the disadvantage of active materials being easily separated from the collector due to the volume effect. However, many reports of flexible freestanding electrodes lack long‐term cycling stability. Here, 3 different silicon‐based freestanding electrodes are designed and find that the freestanding electrode with surface assembly dominated by electrostatic interactions can significantly improve long‐term cycling stability. Owing to better mechanical properties, this surface‐assembled electrode demonstrates unique flexibility. The conductive framework and unique void structure not only reveal the excellent lithium‐ion diffusion capability and charge‐transfer kinetics but also provide ample space for the volume expansion of the silicon‐based material, which endows electrodes with excellent electrochemical performance. With 2 folds, the capacity remains at 471 mA h g−1 after 1000 cycles (0.5 A g−1). In addition, the as‐prepared flexible pouch cell maintains high capacity and cycling stability after folding, with an average capacity degradation of only 0.01% per cycle during 1000 cycles, highlighting its considerable potential in the development of flexible devices. Remarkably, such interfacial assembly on the fiber surface also enables the modulation of multilayer assembly. [ABSTRACT FROM AUTHOR]

Aluminosilicate (Al‐SiO2) thin films with vertically aligned mesochannels were successfully synthesized on Indium Tin Oxide (ITO) electrodes and employed for the immobilization of a cationic Ru(II) water oxidation catalyst without requiring linker groups. Optimal synthesis conditions yielded uniform mesoporous Al‐SiO2 films with tunable Al content, high surface area (568 m2/g), 3.94 nm pore size, and 155 nm thickness. Electrochemical studies confirmed the presence of the immobilized Ru complex undergoing diffusion‐controlled Ru(III/II) and Ru(IV/III) electron transfer. The Ru loading reached 4.71 nmol/cm2 at Si/Al=9.6, with higher Al content enhancing loading amounts via cation exchange. The Ru‐modified electrode exhibited high electrocatalytic water oxidation activity, achieving 75.3 % Faradaic efficiency and a turnover number of 298.6 for O2 evolution for 1 hour. This work provides a new approach to construct porous environments on an electrode surface to immobilize positively charged transition‐metal complexes as catalysts, offering potential applications in the development of electrocatalytic systems for energy conversion. [ABSTRACT FROM AUTHOR]

Gene therapy has the potential to facilitate targeted expression of therapeutic proteins to promote cartilage regeneration in osteoarthritis (OA). The dense, avascular, aggrecan‐glycosaminoglycan (GAG) rich negatively charged cartilage, however, hinders their transport to reach chondrocytes in effective doses. While viral vector mediated gene delivery has shown promise, concerns over immunogenicity and tumorigenic side‐effects persist. To address these issues, this study develops surface‐modified cartilage‐targeting exosomes as non‐viral carriers for gene therapy. Charge‐reversed cationic exosomes are engineered for mRNA delivery by anchoring cartilage targeting optimally charged arginine‐rich cationic motifs into the anionic exosome bilayer by using buffer pH as a charge‐reversal switch. Cationic exosomes penetrated through the full‐thickness of early‐stage arthritic human cartilage owing to weak‐reversible ionic binding with GAGs and efficiently delivered the encapsulated eGFP mRNA to chondrocytes residing in tissue deep layers, while unmodified anionic exosomes do not. When intra‐articularly injected into destabilized medial meniscus mice knees with early‐stage OA, mRNA loaded charge‐reversed exosomes overcame joint clearance and rapidly penetrated into cartilage, creating an intra‐tissue depot and efficiently expressing eGFP; native exosomes remained unsuccessful. Cationic exosomes thus hold strong translational potential as a platform technology for cartilage‐targeted non‐viral delivery of any relevant mRNA targets for OA treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] Breathing and urination, are vital physiological activities of the human body, continuous real-time monitoring of these physiological behaviors could offer timely feedback on an individual's health status. However, current monitoring techniques predominantly rely on cumbersome and intricate medical apparatuses, posing challenges in adapting to the diverse requirements of multi-scenario detection. Consequently, there is a growing interest in developing wearable devices capable of monitoring breathing and urination. In this work, we developed a multifunctional sensor integrating humidity and pressure sensing modes using a simple dip-coating process. By introducing sodium carboxymethyl cellulose and conductive polyaniline hybrid intercalation between MXene layers, a stable conductive network is established through hydrogen bonds and electrostatic interactions among materials. The overall electromechanical properties of the composites will be well improved. And, the effects of different conductive filler ratios and the number of dipping times on the construction of conductive networks are investigated. The multifunctional sensor exhibited improved sensing characteristics, including detecting pressures up to 532 kPa and a sensitivity of 19.58 kPa−1. Furthermore, it also demonstrates good humidity-sensing capabilities. Tests on volunteers demonstrated the potential in the detection of breathing and urination. In addition, the sensors are capable of transmitting Morse code. This interesting application will offer the possibility of normal communication for people with speech impairments. Given its utility and sustainability, the sensor has potential for applications in wearable health monitoring, intelligent life and telemedicine. [ABSTRACT FROM AUTHOR]

The insulin‐degrading enzyme (IDE) plays a significant role in the degradation of the amyloid beta (Aβ), a peptide found in the brain regions of the patients with early Alzheimer's disease. Adenosine triphosphate (ATP) allosterically regulates the Aβ‐degrading activity of IDE. The present study investigates the electrostatic interactions between ATP‐IDE at the allosteric site of IDE, including thermostabilities/flexibilities of IDE residues, which have not yet been explored systematically. This study applies the quantum mechanics/molecular mechanics (QM/MM) to the proposed computational model for exploring electrostatic interactions between ATP and IDE. Molecular dynamic (MD) simulations are performed at different temperatures for identifying flexible and thermostable residues of IDE. The proposed computational model predicts QM/MM energy‐minimised structures providing the IDE residues (Lys530 and Asp385) with high binding affinities. Considering root mean square fluctuation values during the MD simulations at 300.00 K including heat‐shock temperatures (321.15 K and 315.15 K) indicates that Lys530 and Asp385 are also the thermostable residues of IDE, whereas Ser576 and Lys858 have high flexibilities with compromised thermostabilities. The present study sheds light on the phenomenon of biological recognition and interactions at the ATP‐binding domain, which may have important implications for pharmacological drug design. The proposed computational model may facilitate the development of allosteric IDE activators/inhibitors, which mimic ATP interactions. [ABSTRACT FROM AUTHOR]

Transmembrane delivery of biologically active nucleic acids is an important process in cells and has inspired one to develop advanced drug delivery techniques. In this contribution, molecular‐level single‐stranded nucleic acid transmembrane carriers are reported based on 3.2 nm long Huc's foldamers (AOrnQ3Q3)8 and (mQ3Q2)8 with linearly and helically aligned positive charges, respectively. These two foldamers not only show very strong DNA affinity via electrostatic interactions but also discriminatively bind single‐stranded DNA (ss‐DNA) and double‐stranded DNA (ds‐DNA), corroborating the importance of precise charge arrangement in the electrostatic interactions. More importantly, these two foldamers are capable of efficiently transporting ss‐DNA across the lipid membranes, and the ss‐DNA transport activity of (AOrnQ3Q3)8 with linearly aligned charges is higher than that of (mQ3Q2)8 with helically aligned charges. Thus a type of novel single‐stranded nucleic acid transmembrane molecular carriers based on positively charged helical foldamers are introduced. Further, effective and enhanced expression in EGFP‐mRNA transfection experiments strongly demonstrates the potential of positively charged foldamers for RNA transmembrane transport and therapy. [ABSTRACT FROM AUTHOR]

Chemical compounds belonging to the quinone class are known for their cyclic diketone structures. Anthraquinone derivatives have been used as sensing materials and dyes or pigments. The spectroscopic and voltammetric sensing capacity of 1-amino-4-hydroxy-9,10-anthraquinone was utilized to sense 2-bromobenzene-sulfonyl chloride, 4-nitrobenzene-sulfonyl chloride, benzoyl chloride, 2-chloro-benzoyl chloride and 4-bromo-benzoyl chloride. These substituted acyl chlorides and nitrobenzene sulfonyl chloride are important intermediates in various reactions, and the product formation is highly dependent on their concentration. Therefore, it is crucial to take special care as all these compounds are carcinogenic. All studies were carried out in ethanol solvent. Results showed that 1-AHAQ could be effectively used as a UV–visible sensor for sensing 2-bromo benzene sulfonyl chloride. 1-AHAQ demonstrates good results as a fluorescence sensor for sensing 4-bromobenzene-sulfonyl chloride and behaves as a good voltammetric sensor for sensing 4-nitrobenzene sulfonyl chloride. [ABSTRACT FROM AUTHOR]

Adenine base editors (ABEs), consisting of CRISPR Cas nickase and deaminase, can chemically convert the A:T base pair to G:C. ABE8e, an evolved variant of the base editor ABE7.10, contains eight directed evolution mutations in its deaminase TadA8e that significantly increase its base editing activity. However, the functional implications of these mutations remain unclear. Here, we combined molecular dynamics (MD) simulations and experimental measurements to investigate the role of the directed-evolution mutations in the base editing catalysis. MD simulations showed that the DNA-binding affinity of TadA8e is higher than that of the original deaminase TadA7.10 in ABE7.10 and is mainly driven by electrostatic interactions. The directed-evolution mutations increase the positive charge density in the DNA-binding region, thereby enhancing the electrostatic attraction of TadA8e to DNA. We identified R111, N119 and N167 as the key mutations for the enhanced DNA binding and confirmed them by microscale thermophoresis (MST) and in vivo reversion mutation experiments. Unexpectedly, we also found that the directed mutations improved the thermal stability of TadA8e by ~ 12 °C (Tm, melting temperature) and that of ABE8e by ~ 9 °C, respectively. Our results demonstrate that the directed-evolution mutations improve the substrate-binding ability and protein stability of ABE8e, thus providing a rational basis for further editing optimisation of the system. [ABSTRACT FROM AUTHOR]

The aim of this study was to understand the effect of electromagnetic field (EMF) and ionic strength on the electrostatic interactions between β-lactoglobulin(β-lg) and gum Arabic (GA). Therefore, different EMF intensities (5.2, 6.4, 7.6, 8.8, and 10 mT) and NaCl concentrations (30, 35, and 40 mM) were used. The turbidimetric results showed that an increase in the EMF intensity shifted the curves to more acidic regions in comparison to the control sample. In other words, more interactions occurred in the EMF-treated samples while addition of salt distinctly decreased the turbidity and inhibited the interaction. The particle size observations were evaluated by static light scattering machine (SLS). The results showed that the particle size significantly increased (up to 0.753 ± 0.01 μm) by raising the EMF intensities to 10 mT. The addition of NaCl at a concentration of 30 mM showed a slight increase in the particle size diameter. By increasing the salt concentration to 35 and 40 mM, a decrease in the particle diameter was observed which could be due to the reduction in protein/polysaccharide reaction as a result of the prohibiting effect of salts. SEM micrographs revealed almost the same structures in the EMF-treated and untreated samples. However, more aggregation was observed in EMF-treated samples. The presence of salt also established small aggregations. This study showed that EMF can have interesting effects on protein/polysaccharide interactions and formation of particles used as delivery systems. [ABSTRACT FROM AUTHOR]

The bottom-up fabrication of supramolecular and self-assembly on various substrates has become an extremely relevant goal to achieve prospects in the development of nanodevices for electronic circuitry or sensors. One of the branches of this field is the self-assembly of functional molecular components driven through non-covalent interactions on the surfaces, such as van der Waals (vdW) interactions, hydrogen bonding (HB), electrostatic interactions, etc., allowing the controlled design of nanostructures that can satisfy the requirements of nanoengineering concepts. In this context, non-covalent interactions present opportunities that have been previously explored in several molecular systems adsorbed on surfaces, primarily due to their highly directional nature which facilitates the formation of well-ordered structures. Herein, we review a series of research works by combining STM (scanning tunneling microscopy) with theoretical calculations, to reveal the processes used in the area of self-assembly driven by molecule Landers equipped with functional groups on the metallic surfaces. Combining these processes is necessary for researchers to advance the self-assembly of supramolecular architectures driven by multiple non-covalent interactions on solid surfaces. [ABSTRACT FROM AUTHOR]

In order to understand the formation process and interaction mechanism of complexes between ovalbumin (OVA) and fucoidan (FUC), turbidity titration, zeta potential measurement, circular dichroism (CD) spectroscopy, fluorescence spectroscopy and dynamic rheometer analysis were used to analyze the phase behavior and critical pH values (pHc, pHφ1 and pHmax) of OVA-FUC complexes. The zeta potential results showed that the that the critical pH for the formation of composite aggregates was closely related to the ratio of OVA to FUC and salt concentration. The zeta potential analysis indicated that the formation of composite aggregates was mainly driven by electrostatic interaction. As the OVA/FUC ratio increased, the critical pH shifted to a higher value. Low salt concentrations (c(NaCl) < 100 mmol/L) promoted the formation of aggregates, while high salt concentrations (c(NaCl) ≥ 100 mmol/L) significantly decreased the critical pH due to electrostatic shielding. Under acidic conditions (pH 4.5), maximum viscoelasticity was observedat an OVA/FUC ratio of 20:1 (m/m) and NaCl concentration of 400 mmol/L. Our study provides a theoretical basis for the development of functional products based on sulfated polysaccharide and egg white protein.

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Oil/water (O/W) emulsions were prepared using the complex of quarternized cellulose nanofiber (QCNF) and octanoyl gelatin (OC−Gel) as an emulsifier, and the effect of pH value on their stability was investigated. OC−Gel was prepared through a condensation reaction, confirmed by 1H Nuclear Magnetic Resonance (NMR) and Fourier Transform Infrared (FT−IR) spectroscopy. It reduced air/water interfacial tension more effectively than unmodified gelatin. The complexation degree of OC−Gel and QCNF, measured by optical density, showed its maximum at a QCNF/OC−Gel mass ratio of 1/8 when the pH value of the medium was 7.4, and it increased in a saturated manner with increasing pH value. The signals of QCNF were found in the FT−IR and X−ray diffraction spectra of the complex, suggesting that the positively charged CNF were included in the OC−Gel−based complex. The complex formed a rough surface with smooth debris because the surface roughness of the complex aggregation reflected that of both QCNF and OC−Gel aggregation. QCNF could stabilize oil droplets to form a Pickering O/W emulsion. The complex of QCNF/OC−Gel was also a good emulsifier. QCNF and the complex were as potent as OC−Gel in emulsifying mineral oil in water. Most of the droplets fell within 5–25 µm, regardless of what the emulsifier was. The emulsion stabilized with OC−Gel increased in its oil droplet size more than two times in 20 days at all the pH vales tested (pH 3, 5, 7.4, 9), whereas the emulsion stabilized with QCNF remained almost constant in size during the same period regardless of the pH values. The droplet size of emulsion stabilized with the QCNF/OC−Gel complex did not change appreciably when the pH value was 5, 7.4, and 9. The complex seemed to act as a capsule wall and prevent the coalescence of the droplets. However, it increased dramatically due to the coalescence at pH 3, possibly because the complex could be dissolved under a strong acidic condition. [ABSTRACT FROM AUTHOR]

Catalytic oxidative desulfurization (ODS) using titanium silicate catalysts has emerged as an efficient technique for the complete removal of organosulfur compounds from automotive fuels. However, the precise control of highly accessible and stable-framework Ti active sites remains highly challenging. Here we reveal for the first time by using density functional theory calculations that framework hexa-coordinated Ti (TiO6) species of mesoporous titanium silicates are the most active sites for ODS and lead to a lower-energy pathway of ODS. A novel method to achieve highly accessible and homogeneously distributed framework TiO6 active single sites at the mesoporous surface has been developed. Such surface framework TiO6 species exhibit an exceptional ODS performance. A removal of 920 ppm of benzothiophene is achieved at 60°C in 60 min, which is 1.67 times that of the best catalyst reported so far. For bulky molecules such as 4,6-dimethyldibenzothiophene (DMDBT), it takes only 3 min to remove 500 ppm of DMDBT at 60°C with our catalyst, which is five times faster than that with the current best catalyst. Such a catalyst can be easily upscaled and could be used for concrete industrial application in the ODS of bulky organosulfur compounds with minimized energy consumption and high reaction efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] Adjusting the water content and mechanical properties of polyelectrolyte coacervates for optimal underwater adhesion requires simultaneous control of the macromolecular design and the type and concentration of the salt used. Using synthetic or bio-inspired polymers to make coacervates often involves complicated chemistries and large variations in salt concentration. The underwater adhesiveness of simple, bio-sourced coacervates can be tuned with relatively small variations in salt concentration. Bio-sourced polymers can also impart beneficial biological activities to the final material. We made complex coacervates from charged chitosan (CHI) and hyaluronic acid (HA) with NaCl as the salt. Their water content and viscoelastic properties were investigated to identify the formulation with optimal underwater adhesion in physiological conditions. The coacervates were also studied in antibacterial and cytotoxicity experiments. As predicted by linear rheology, the CHI-HA coacervates at 0.1 and 0.2 M NaCl had the highest pull-off adhesion strengths of 44.4 and 40.3 kPa in their respective supernatants. In-situ physical hardening of the 0.2 M coacervate upon a salt switch in 0.1 M NaCl resulted in a pull-off adhesion strength of 62.9 kPa. This material maintained its adhesive properties in physiological conditions. Finally, the optimal adhesive was found to be non-cytotoxic and inherently antimicrobial through a chitosan release-killing mechanism. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Self‐assembly of inorganic nanoparticles (NPs) is an essential tool for constructing structured materials with a wide range of applications. However, achieving ordered assembly structures with externally programmable properties in binary NP systems remains challenging. In this work, we assemble binary inorganic NPs into hierarchically pH‐responsive alternating copolymer‐like nanostructures in an aqueous medium by engineering the interparticle electrostatic interactions. The polymer‐grafted NPs bearing opposite charges are viewed as nanoscale monomers ("nanomers"), and copolymerized into alternating nano‐copolymers (ANCPs) driven by the formation of interparticle "bonds" between nanomers. The resulting ANCPs exhibit reversibly responsive "bond" length (i.e. the distance between nanomers) in response to the variation of pH in a range of ~7–10, allowing precise control over the surface plasmon resonance of ANCPs. Moreover, specific interparticle "bonds" can break up at pH≥11, leading to the dis‐assembly of ANCPs into molecule‐like dimers and trimers. These dimeric and trimeric structures can reassemble to form ANCPs owing to the resuming of interparticle "bonds", when the pH value of the solution changes from 11 to 7. The hierarchically responsive nanostructures may find applications in such as biosensing, optical waveguide, and electronic devices. [ABSTRACT FROM AUTHOR]

Insulin and immunoglobulin therapy is commonly administered through injections that are invasive and painful. They cannot be taken orally because digestive enzymes break them down. To protect against enzymes, drug molecules may be "packed", which decreases interaction of the active surface of the molecule with the environment. Silica nanoparticles (SiO2) may be used to attach proteins like insulin or immunoglobulin for use in drug delivery. They are stable and biocompatible. Exposing SiO2 nanoparticles to UV radiation may control molecule–nanoparticle attachment because of their electrostatic interactions. This study demonstrates the influence of UV radiation of SiO2 nanoparticles on insulin and immunoglobulin molecule attachment. Alteration of the surface electric potential of SiO2 nanoparticles by UV radiation was determined using electron work function measurements. Influence of radiation on formation of molecule-nanoparticle complexes was assessed by spectrophotometry of their sedimentation rate in solution. Increasing UV exposure time negatively charges the surfaces of SiO2 nanoparticles. Insulin exhibits better adsorption with SiO2 nanoparticles compared to immunoglobulin, likely due to favourable conditions promoting attractive electrostatic interactions. Longer UV exposure weakens insulin adsorption but does not significantly affect immunoglobulin adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] The mucoadhesive characteristics of amphoteric polymers (also known as polyampholytes) can vary and are influenced by factors such as the solution's pH and its relative position against their isoelectric point (pH IEP). Whilst the literature contains numerous reports on mucoadhesive properties of either cationic or anionic polymers, very little is known about these characteristics for polyampholytes Here, two amphoteric polymers were synthesized by reaction of linear polyethylene imine (l -PEI) with succinic or phthalic anhydride and their mucoadhesive properties were compared to bovine serum albumin (BSA), selected as a natural polyampholyte. Interactions between these polymers and porcine gastric mucin were studied using turbidimetric titration and isothermal titration calorimetry across a wide range of pHs. Model tablets were designed, coated with these polymers and tested to evaluate their adhesion to porcine gastric mucosa at different pHs. Moreover, a retention study using fluorescein isothiocyanate (FITC)-labelled polyampholytes deposited onto mucosal surfaces was also conducted All these studies indicated the importance of solution pH and its relative position against pH IEP in the mucoadhesive properties of polyampholytes. Both synthetic and natural polyampholytes exhibited strong interactions with mucin and good mucoadhesive properties at pH < pH IEP. [ABSTRACT FROM AUTHOR]

A key biophysical process in biological systems, liquid–liquid phase separation (LLPS) is responsible for constructing membrane-less organelles and modulating cellular activities. The biophysical mechanisms underlying LLPS are explored in this paper, with an emphasis on multivalent interactions, entropy-driven processes, and how they affect cellular organization. We investigate the impact of external stimuli on phase behavior and clarify the physiological roles of biomolecular condensates, from stress response modulation to gene expression regulation. In addition, we study dysregulated LLPS in human disorders, providing information about possible therapeutic targets and approaches to innovative therapeutics. Through this interdisciplinary approach, we aim to improve our knowledge of LLPS and its effects on health and illness, opening the door to new therapeutic approaches that focus on the behavior of proteins and the structure of cells. [ABSTRACT FROM AUTHOR]

The impact of molecular interactions on the physical properties of extruded pea protein isolate (PPI) is investigated by adding interaction-modulating compounds to the matrix premix and studying the resulting variations in mechanical and physicochemical properties. Blends of PPI (water content 50% w/w) containing either sodium phosphate, urea, sodium dodecylsulphate and β-mercaptoethanol, as well as with all four compounds and only with deionized water (control) were extruded into thin strands (diameter ∼2.4 mm) using a lab-scale twin-screw extruder. The hardness from texture profile analysis (TPA) was the lowest for matrices extruded with β-mercaptoethanol and with all four chemicals, and highest for the control sample. The water holding capacity (WHC) of the matrices is lowest for the β-mercaptoethanol-containing matrix. These results are corroborated by the absorbance of the supernatant at λ = 280 and 600 nm. Our results confirm the importance of disulfide bonds in texturized PPI and show that hydrophobic and electrostatic interactions play auxiliary roles in modulating the properties of extruded PPI matrices. Our approach opens novel ways to modulate the physical properties of texturized plant protein matrices and thereby control their texture. [ABSTRACT FROM AUTHOR]

Abstract Transmembrane delivery of biologically active nucleic acids is an important process in cells and has inspired one to develop advanced drug delivery techniques. In this contribution, molecular‐level single‐stranded nucleic acid transmembrane carriers are reported based on 3.2 nm long Huc's foldamers (AOrnQ3Q3)8 and (mQ3Q2)8 with linearly and helically aligned positive charges, respectively. These two foldamers not only show very strong DNA affinity via electrostatic interactions but also discriminatively bind single‐stranded DNA (ss‐DNA) and double‐stranded DNA (ds‐DNA), corroborating the importance of precise charge arrangement in the electrostatic interactions. More importantly, these two foldamers are capable of efficiently transporting ss‐DNA across the lipid membranes, and the ss‐DNA transport activity of (AOrnQ3Q3)8 with linearly aligned charges is higher than that of (mQ3Q2)8 with helically aligned charges. Thus a type of novel single‐stranded nucleic acid transmembrane molecular carriers based on positively charged helical foldamers are introduced. Further, effective and enhanced expression in EGFP‐mRNA transfection experiments strongly demonstrates the potential of positively charged foldamers for RNA transmembrane transport and therapy.

The widespread utilization of plastic products ineluctably leads to the ubiquity of nanoplastics (NPs), causing potential risks for aquatic environments. Interactions of NPs with mineral surfaces may affect NPs transport, fate and ecotoxicity. This study aims to investigate systematically the deposition and aggregation behaviors of carboxylated polystyrene nanoplastics (COOH-PSNPs) by four types of clay minerals (illite, kaolinite, Na-montmorillonite, and Ca-montmorillonite) under various solution chemistry conditions (pH, temperature, ionic strength and type). Results demonstrate that the deposition process was dominated by electrostatic interactions. Divalent cations (i.e., Ca2+, Mg2+, Cd2+, or Pb2+) were more efficient for screening surface negative charges and compressing the electrical double layer (EDL). Hence, there were significant increases in deposition rates of COOH-PSNPs with clay minerals in suspension containing divalent cations, whereas only slight increases in deposition rates of COOH-PSNPs were observed in monovalent cations (Na+, K+). Negligible deposition occurred in the presence of anions (F−, Cl−, NO3−, CO32−, SO42−, or PO43−). Divalent Ca2+ could incrementally facilitate the deposition of COOH-PSNPs through Ca2+-assisted bridging with increasing CaCl2 concentrations (0–100 mM). The weakened deposition of COOH-PSNPs with increasing pH (2.0–10.0) was primarily attributed to the reduce in positive charge density at the edges of clay minerals. In suspensions containing 2 mM CaCl2, increased Na+ ionic strength (0–100 mM) and temperature (15–55 ◦C) also favored the deposition of COOH-PSNPs. The ability of COOH-PSNPs deposited by four types of clay minerals followed the sequence of kaolinite > Na-montmorillonite > Ca-montmorillonite > illite, which was related to their structural and surface charge properties. This study revealed the deposition behaviors and mechanisms between NPs and clay minerals under environmentally representative conditions, which provided novel insights into the transport and fate of NPs in natural aquatic environments.

Natural polysaccharides can serve as carriers of genes owing to their intrinsic biocompatibility, biodegradability, and low toxicity. Additionally, they can be easily chemically modified, e.g., through grafting, leading to hybrid synthetic–biological copolymers with additional functionalities. In this work we report on the electrostatic interaction between a chitosan-g-poly(N-isopropylacrylamide) (Chit-g-PNIPAM) copolymer and DNA macromolecules of different lengths (i.e., 50 and 2000 bp), towards the construction of polyplexes that can serve as potential gene delivery systems. At the basic science level, the work aims to elucidate the effects of DNA length on the structural and physicochemical properties of the thermoresponsive hybrid macromolecular assemblies. The protonated amino groups on the chitosan backbone enable electrostatic binding with the anionic phosphate groups of the DNA molecules, while the PNIPAM side chains are expected to impart thermoresponsive properties to the formed polyplexes. Different amino to phosphate group (N/P) mixing ratios were examined, aiming to produce stable dispersions. The physicochemical properties of the resulting polyplexes were investigated by dynamic and electrophoretic light scattering (DLS and ELS), while their morphology was studied by scanning-transmission electron microscopy (STEM). Moreover, their response to changes in temperature and ionic strength, as well as their stability against biological media, was also examined. Finally, the binding affinity of the copolymer towards DNA was evaluated through fluorescence spectroscopy, using ethidium bromide quenching assays, while infrared spectroscopy was used to investigate the structure of the incorporated DNA chains.

Perfluoroalkyl and polyfluoroalkyl substances (PFASs) are persistent compounds characterized by stable C−F bonds giving them high thermal and chemical stability. Numerous studies have highlighted the presence of PFASs in the environment, surface waters and animals and humans. Exposure to these chemicals has been found to cause various health effects and has necessitated the need to develop methods to remove them from the environment. To date, the use of photocatalytic degradation and membrane separation to remove PFASs from water has been widely studied; however, these methods have drawbacks hindering them from being applied at full scale, including the recovery of the photocatalyst, uneven light distribution and membrane fouling. Therefore, to overcome some of these challenges, there has been research involving the coupling of photocatalysis and membrane separation to form photocatalytic membrane reactors which facilitate in the recovery of the photocatalyst, ensuring even light distribution and mitigating fouling. This review not only highlights recent advancements in the removal of PFASs using photocatalysis and membrane separation but also provides comprehensive information on the integration of photocatalysis and membrane separation to form photocatalytic membrane reactors. It emphasizes the performance of immobilized and slurry systems in PFAS removal while also addressing the associated challenges and offering recommendations for improvement. Factors influencing the performance of these methods will be comprehensively discussed, as well as the nanomaterials used for each technology. Additionally, knowledge gaps regarding the removal of PFASs using integrated photocatalytic membrane systems will be addressed, along with a comprehensive discussion on how these technologies can be applied in real-world applications.

In the critical domain of wastewater treatment, the development of cost-effective, durable, and recyclable adsorbents with high adsorption capacities remains a significant challenge. This study introduces a novel magnetic bimetallic Metal–Organic Framework (MOF) adsorbent, MZIF-67-Co/Cu, doped with copper ions. The MZIF-67-Co/Cu adsorbent was successfully synthesized and structurally characterized, demonstrating remarkable selectivity for removing methyl orange (MO) from water. This high selectivity is attributed to the adsorbent’s high porosity and Lewis base properties at the coordinating metal ion center. The incorporation of Cu ions significantly enhances the porous architecture and increases the number of metal adsorption sites, leading to an impressive maximum MO adsorption capacity of 39.02 mg/g under optimized conditions (0.5 g/L adsorbent concentration, pH 3.0, 250 rpm agitation speed, adsorption time > 10 min). The adsorption kinetics closely follow the pseudo-second-order model, and the isotherm data fit well with the Langmuir model. The primary adsorption mechanisms involve electrostatic attraction and mesoporous interaction. This study highlights MZIF-67-Co/Cu as a highly efficient adsorbent with magnetic recovery capabilities, positioning it as a promising candidate for addressing critical issues in wastewater treatment.

In this study, it is demonstrated that CsPbBr3 perovskite nanocrystals (NCs) can enhance the overall performances of photomultiplication‐type organic photodiodes (PM‐OPDs). The proposed approach enables the ionic‐polarizable CsPbBr3 NCs to be evenly distributed throughout the depletion region of Schottky junction interface, allowing the entire trapped electrons within the depletion region to be stabilized, in contrast to previously reported interface‐limited strategies. The optimized CsPbBr3‐NC‐embedded poly(3‐hexylthiophene‐diyl)‐based PM‐OPDs exhibit exceptionally high external quantum efficiency, specific detectivity, and gain–bandwidth product of 2,840,000%, 3.97 × 1015 Jones, and 2.14 × 107 Hz, respectively. 2D grazing‐incidence X–ray diffraction analyses and drift–diffusion simulations combined with temperature‐dependent J–V characteristic analyses are conducted to investigate the physics behind the success of CsPbBr3‐NC‐embedded PM‐OPDs. The results show that the electrostatic interactions generated by the ionic polarization of NCs effectively stabilize the trapped electrons throughout the entire volume of the photoactive layer, thereby successfully increasing the effective energy depth of the trap states and allowing efficient PM mechanisms. This study demonstrates how a hybrid‐photoactive‐layer approach can further enhance PM‐OPD when the functionality of inorganic inclusions meets the requirements of the target device. [ABSTRACT FROM AUTHOR]

Low critical solution temperature (LCST) of commonly used thermoresponsive polymers in water is basically dominated by hydrophobic interactions. Herein, a novel thermoresponsive system based on electrostatic interactions is reported. By simply loading aluminum chloride (AlCl3) into non‐responsive poly(2‐hydroxyethyl acrylate) (PHEA) hydrogels, PHEA‐Al gels turn to have reversible thermoresponsive behavior between transparent and opaque without any volume change. Further investigations by changing metal ion‐polymer compositions unravel the necessity of specific electrostatic interactions, namely, cation‐dipole bonding interactions between hydroxy groups and trivalent metal ions. The thermoresponsive hydrogel demonstrates high transparency (≈95%), excellent luminous modulation capability (>98%), and cyclic reliability, suggesting great potential as an energy‐saving material. Although LCST control by salt addition is widely known, salt‐induced expression of thermoresponsiveness has barely been discussed before. This design provides a new approach of easy fabrication, low cost, and scalability to develop stimuli‐responsive materials. [ABSTRACT FROM AUTHOR]

This work presents a framework for evaluating hybrid nanoflowers using Burkholderia cepacia lipase. It was expanded on previous findings by testing lipase hybrid nanoflowers (hNF-lipase) formation over a wide range of pH values (5–9) and buffer concentrations (10–100 mM). The free enzyme activity was compared with that of hNF-lipase. The analysis, performed by molecular docking, described the effect of lipase interaction with copper ions. The morphological characterization of hNF-lipase was performed using scanning electron microscopy. Fourier Transform Infrared Spectroscopy performed the physical–chemical characterization. The results show that all hNF-lipase activity presented values higher than that of the free enzyme. Activity is higher at pH 7.4 and has the highest buffer concentration of 100 mM. Molecular docking analysis has been used to understand the effect of enzyme protonation on hNF-lipase formation and identify the main the main binding sites of the enzyme with copper ions. The hNF-lipase nanostructures show the shape of flowers in their micrographs from pH 6 to 8. The spectra of the nanoflowers present peaks typical of the amide regions I and II, current in lipase, and areas with P–O vibrations, confirming the presence of the phosphate group. Therefore, hNF-lipase is an efficient biocatalyst with increased catalytic activity, good nanostructure formation, and improved stability. [ABSTRACT FROM AUTHOR]

Background: Soil organisms influence pedogenesis on a molecular level through the production of biopolymers which interact with soil minerals depending on their molecular properties. Specifically, biopolymers impact structure formation by inhibiting aggregation as a separation agent or promoting aggregation as a bridging agent. Mucus is a biopolymer excreted by earthworms that consists mainly of proteins, polysaccharides, and, to a lesser extent, lipids. However, despite earthworms' fundamental contribution to soil quality and structuring via bioturbation, the role of mucus in aggregation still has to be unraveled. Aims: Our study explores the role of cutaneous earthworm mucus (CEM) of Lumbricus terrestris L. for the formation of organo–mineral associations and aggregates, a sub‐process of pedogenesis. Methods: We conducted batch experiments with goethite and CEM at different pH values and varying CEM concentrations to form mucus–goethite associations. Employing the newly formed mucus–goethite associations, we explored the (homo‐/hetero‐)aggregation with quartz particles as a function of the loading of surfaces with mucus‐C and CEM concentrations in solution. Results: Our results suggest that the molecular structure of CEM constituents (especially proteins) is sensitive to pH. We found that the adsorption of CEM to goethite depends on pH and concentration. Polysaccharides of CEM adsorbed preferentially under acidic conditions (pH 3) and at low CEM concentration (6 mg mucus‐C L–1). In contrast, stronger adsorption of proteins was observed at higher CEM concentrations (30 mg mucus‐C L–1). In subsequent aggregation experiments, the hetero‐aggregation rate of organo–mineral associations and quartz decreased at low C‐loadings. Conversely, the rate increased at high loadings compared to the CEM‐free reference. Furthermore, electrostatic/steric repulsion (separation agent) inhibited the aggregation between goethite particles at high CEM concentrations in the solution (mineral/mucus ratio of 17). However, at a low CEM supply (mineral/mucus ratio of >83), CEM took the role of a bridging agent. Conclusions: The composition, function, and (im‐)mobilization of CEM and corresponding organo–mineral associations in earthworm‐influenced soil structures are shaped by the structure/reactivity of CEM affected by environmental parameters. Formation and aggregation of mucus–mineral associations contribute to nutrient/carbon storage and are involved in the structure formation in soil. [ABSTRACT FROM AUTHOR]

Dyes are significant contributors to the chemical oxygen demand of the wastewater produced by textile industries. In the current study, naturally occurring, inexpensive, non-hazardous clay was pillared and used to remove Acid Green 25 dye (AG) from aqueous solutions. The pseudo-second-order model provided a better fit to describe the adsorption kinetics data for AG, with a rate constant of 9.82 × 10−3 g/mg min. Langmuir isotherm provided a better fit for describing the adsorption isotherm of the AG dye. Thermodynamic analysis revealed that adsorption was exothermic with an enthalpy change of −48 kJ/mol. The effects of pH, adsorbent dosage, and initial concentration of AG dye on adsorption capacity were analyzed, and an empirical model was developed using the response surface methodology approach. Optimization studies revealed that a maximum adsorption capacity of 105.15 mg/g for the AG dye could be achieved at a pH of 2, an adsorbent dosage of 1.5 g/L and an initial dye concentration at its upper limit of 200 mg/L. The adsorbent could be regenerated and reused up to three adsorption cycles, and the desorbed dye and treated water may be reused in the dyeing process, thereby making the entire operation circular. Circularity reduces the cost of production and makes the process more sustainable. Mechanistic insights revealed that electrostatic interaction was the driving force for the adsorption of AG dye. In this work, it has been demonstrated that after pillaring, clay-based material may be used as an effective adsorbent for treating dye-containing wastewater. [ABSTRACT FROM AUTHOR]

Polymerization‐induced self‐assembly (PISA) enables the simultaneous growth and self‐assembly of block copolymers in one pot and therefore has developed into a high‐efficiency platform for the preparation of polymer assemblies with high concentration and excellent reproducibility. During the past decade, the driving force of PISA has extended from hydrophobic interactions to other supramolecular interactions, which has greatly innovated the design of PISA, enlarged the monomer/solvent toolkit, and endowed the polymer assemblies with intrinsic dynamicity and responsiveness. To unravel the important role of driving forces in the formation of polymeric assemblies, this review summarized the recent development of PISA from the perspective of driving forces. Motivated by this goal, here we give a brief overview of the basic principles of PISA and systematically discuss the various driving forces in the PISA system, including hydrophobic interactions, hydrogen bonding, electrostatic interactions, and π‐π interactions. Furthermore, PISA systems that are driven and regulated by crystallization or liquid crystalline ordering were also highlighted. [ABSTRACT FROM AUTHOR]

Recent developments in asymmetric catalysis involve the heterogeneization of chiral complexes so that they can be easily immobilized on different supports. This account focuses on procedures that lead to the formation of non-covalent interactions between the chiral active sites and the chosen support, as they generally involve less tedious synthetic modifications and can allow either the chiral catalyst or the support to be easily recovered, at will. As a result, electrostatic interactions between inorganic supports and chiral organometallic complexes have been described to lead to efficient and recoverable catalysts. More recently, other weak interactions, such as π-interactions, but also donor--acceptor complexes, have been implicated for implementation of robust immobilizing procedures. There are also many examples of the use of coordination links, such as those present in metal organic frameworks for supported asymmetric catalysis, which pave the way for efficient cooperative or tandem asymmetric catalysis. [ABSTRACT FROM AUTHOR]

As the most aggressive subtype, triple‐negative breast cancer (TNBC) without definitive targets represents a high probability of metastasis. Nevertheless, the presence of high‐level tumor‐infiltrating lymphocytes in the TNBC tumor microenvironment (TME) suggests patients may benefit from immunotherapy. In this study, bovine α‐lactalbumin coupled with oleic acid that forms tumoricidal lipid–protein complex (BAMLET) is electrostatically stabilized on the surface of amino‐functionalized mesoporous silica nanoparticles (MSN‐NH2). It is found that MSN‐NH2 may cause partial conformational changes of immobilized proteins due to electrostatic interactions. Therefore, BAMLET covered MSN‐NH2 (BMSN) as a drug cargo that can not only induce selectively oncolytic effect but kill tumor cells with rapid kinetics. Moreover, the hemolytic activity of BMSN conjugated with pre‐formed serum protein corona is largely reduced which may avoid the poor hemocompatibility caused by BAMLET. Furthermore, the in vivo study indicates that the combinational use of drug‐loaded BMSN and immune checkpoint small‐molecule inhibitor can efficiently inhibit the growth of solid TNBC tumors and activate immune response by sufficient infiltration of immune cells in the TME and prevent the seeding of circulating tumor cells. Therefore, the constructed BMSN provides an integrated nanotherapeutics and a nanoadjuvant with superior anticancer performance to combat TNBC. [ABSTRACT FROM AUTHOR]

Protein–nanoparticle hybridization can ideally lead to novel biological entities characterized by emerging properties that can sensibly differ from those of the parent components. Herein, the effect of ionic strength on the biological functions of recombinant His-tagged spermine oxidase (i.e., SMOX) was studied for the first time. Moreover, SMOX was integrated into colloidal surface active maghemite nanoparticles (SAMNs) via direct self-assembly, leading to a biologically active nano-enzyme (i.e., SAMN@SMOX). The hybrid was subjected to an in-depth chemical–physical characterization, highlighting the fact that the protein structure was perfectly preserved. The catalytic activity of the nanostructured hybrid (SAMN@SMOX) was assessed by extracting the kinetics parameters using spermine as a substrate and compared to the soluble enzyme as a function of ionic strength. The results revealed that the catalytic function was dominated by electrostatic interactions and that they were drastically modified upon hybridization with colloidal ɣ-Fe2O3. The fact that the affinity of SMOX toward spermine was significantly higher for the nanohybrid at low salinity is noteworthy. The present study supports the vision of using protein–nanoparticle conjugation as a means to modulate biological functions. [ABSTRACT FROM AUTHOR]

A large number of experimental studies have demonstrated that globular proteins can be absorbed from the solution by both polycationic and polyanionic brushes when the net charge of protein globules is of the same or of the opposite sign with respect to that of brush-forming polyelectrolyte chains. Here, we overview the results of experimental studies on interactions between globular proteins and polycationic or polyanionic brushes, and present a self-consistent field theoretical model that allows us to account for the asymmetry of interactions of protein-like nanocolloid particles comprising weak (pH-sensitive) cationic and anionic groups with a positively or negatively charged polyelectrolyte brush. The position-dependent insertion free energy and the net charge of the particle are calculated. The theoretical model predicts that if the numbers of cationic and anionic ionizable groups of the protein are approximately equal, then the interaction patterns for both cationic and anionic brushes at equal offset on the "wrong side" from the isoelectric point (IEP), i.e., when the particle and the brush charge are of the same sign, are similar. An essential asymmetry in interactions of particles with polycationic and polyanionic brushes is predicted when fractions of cationic and anionic groups differ significantly. That is, at a pH above IEP, the anionic brush better absorbs negatively charged particles with a larger fraction of ionizable cationic groups and vice versa. [ABSTRACT FROM AUTHOR]

Messenger RNA (mRNA) therapies have emerged as potent and personalized alternatives to conventional DNA-based therapies. However, their therapeutic potential is frequently constrained by their molecular instability, susceptibility to degradation, and inefficient cellular delivery. This study presents the nanoparticle "ChargeSome" as a novel solution. ChargeSomes are designed to protect mRNAs from degradation by ribonucleases (RNases) and enable cell uptake, allowing mRNAs to reach the cytoplasm for protein expression via endosome escape. We evaluated the physicochemical properties of ChargeSomes using 1H nuclear magnetic resonance, Fourier-transform infrared, and dynamic light scattering. ChargeSomes formulated with a 9:1 ratio of mPEG-b-PLL to mPEG-b-PLL-SA demonstrated superior cell uptake and mRNA delivery efficiency. These ChargeSomes demonstrated minimal cytotoxicity in various in vitro structures, suggesting their potential safety for therapeutic applications. Inherent pH sensitivity enables precise mRNA release in acidic environments and structurally protects the encapsulated mRNA from external threats. Their design led to endosome rupture and efficient mRNA release into the cytoplasm by the proton sponge effect in acidic endosome environments. In conclusion, ChargeSomes have the potential to serve as effective secure mRNA delivery systems. Their combination of stability, protection, and delivery efficiency makes them promising tools for the advancement of mRNA-based therapeutics and vaccines. [ABSTRACT FROM AUTHOR]