Molar Ratio Research Articles

Insights into the Morphological Effects of 1D, 2D, and 3D CoV-Layered Double Hydroxides on Their Electrochemical Performance in Supercapacitors.

In this study, bimetallic cobalt-vanadium-based layered double hydroxide (CoV-LDH) systems were developed by varying the Co/V molar ratios (1:1 and 2:1) and hydrothermal temperatures (120 and 180 °C). Structural analysis by X-ray diffraction (XRD), Raman, and Fourier-transform infrared (FTIR) spectroscopy indicated the successful formation of CoV-LDH with a unique structure and lattice distortions, reflecting the influence of both the metal concentrations and temperature on the crystal and chemical structures of the developed bimetallic systems. Similarly, the field-emission scanning electron microscopy (FESEM) and high resolution transmission electron microscopy (HRTEM) images revealed a flaky 2D nanosheet-like structure for the bimetallic CoV-LDH with a 1:1 ratio prepared at 120 °C (CVL1-120), whereas one-dimensional (1D) and three-dimensional (3D) morphologies were observed for other bimetallic CoV-LDH systems prepared with a different molar ratio (2:1) and/or temperature (180 °C). Electrochemical analysis performed in a three-electrode setup demonstrated a specific capacitance of 314.4 F g-1 at 1 A g-1 current density for CVL1-120, which is ∼4.5 and 5.2 times higher than those of monometallic Co and V-LDH, respectively. In addition, CVL1-120 exhibited an excellent capacitance retention of ∼97% over 5000 charge-discharge cycles with 100% Coulombic efficiency at 10 A g-1. Furthermore, the developed asymmetric device delivered an energy density of 36.5 Wh kg-1 and a power density of 1208.2 W kg-1. This enhanced performance of CVL1-120 was attributed to its two-dimensional (2D) flaky structures, with rich intercalated ions serving as electroactive sites, facilitating enhanced charge storage efficiency and improved stability, making it suitable as an electrode material for sustainable supercapacitors.

Protein Cage-like Vesicles Fabricated via Polymerization-Induced Microphase Separation of Amphiphilic Diblock Copolymers

Highly symmetric protein cages represent one of the most artistic architectures formed by biomolecules. However, the underlying reasons for the formation of some of these architectures remain unknown. The present study aims to investigate the significance behind their morphological formation by fabricating protein cage-like vesicles using a synthetic polymer. The vesicles were synthesized by combining polymerization-induced self-assembly (PISA) with polymerization-induced microphase separation (PIMS), employing an amphiphilic poly(methacrylic acid)-block-poly(n-butyl methacrylate-random-cyclohexyl methacrylate-random-methacrylic acid) diblock copolymer, PMAA-b-P(BMA-r-CMA-r-MAA). The copolymer, with a 60 mol% molar ratio of CMA to the BMA units, produced clathrin-like vesicles with angular windows in their shell, resulting from the segregation of the hard CMA units from the soft BMA matrix in the hydrophobic phase of the vesicle. These vesicles were highly stable against rising temperatures. In contrast, the vesicles with a 30 mol% CMA ratio dissociated upon heating to 50 °C into triskelion-like segments due to intramolecular microphase separation. These findings indicate that designing synthetic polymers can mimic living organ morphologies, aiding in elucidating their morphological significance and inspiring the development of new materials utilizing these morphologies.

Accessing a Carboxyl-Anhydride Molecular Switch-Mediated Recyclable PECT Through Upcycling End-of-Use PET.

Poly(ethylene terephthalate)(PET), with an annual production of exceeding 70 million tons, is mainly utilized in disposable fields and subsequently contribute to severe environmental pollution. Conventional chemical recycling, which typically involves depolymerizing polymer into monomers, is limited due to the intricate recycling process, excess using unrecyclable solvents and low polymer conversion. Inspired by protein's molecular switches, we propose a novel polymer-to-polymer recycling strategy based on polycondensation principles upcycling waste PET to high-value recyclable poly(ethylene-co-1,4-cyclohexanedimethanol terephthalate) derivatives containing molecular switches. Upon deactivating the molecular switch, an acidification reaction occurs within the system, leading to a rapid and controllable reduction in molecular weight due to the imbalance of reactive group. Conversely, activating the molecular switch triggers a ring-closing reaction that detaches acid anhydrides, bringing about equal molar ratio of groups and thereby facilitating an increase in molecular weight. By simply incorporating a molecular switch into condensation products based on melt polycondensation, closed-loop recycling capability is achieved without necessitating excessive organic solvents or complex depolymerization processes. The present study not only presents a novel pathway for end-of-use PET upcycling but also introduces an innovative concept of molecular switching for the closed-loop recyclability of condensation polymers, thereby demonstrating significant potential for large-scale implementation.

Synthesis and Bioactivity of Selenium Nanoparticles from Tussilago farfara L Polysaccharides: Antioxidant Properties and MCF-7 Cell Inhibition.

The present study reports the synthesis of a selenium nanocomplex (Se-TFPs) using purified polysaccharides from Tussilago farfara L (coltsfoot). It evaluates its structural characteristics, physicochemical properties, and inhibitory effects of Michigan Cancer Foundation-7 (MCF-7) breast cancer cells. The influence of processing conditions on nanoparticle size and stability at 25 °C was assessed using particle size and zeta potential measurements. The Se-TFPs were synthesized by optimizing the processing conditions via response surface methodology, yielding nanoparticles with a selenium (Se)-to-polysaccharide mass ratio of 1:13.5, a Se-to-ascorbic acid molar ratio of 1:4.5, a selenite concentration of 10.7 mM, and a reaction time of 4.4 h. The resulting Se-TFPs had an average particle size of 107.2 nm and a zeta potential of -35.1 mV. Structural and physicochemical analyses confirmed successful nanoparticle formation. Compared to TFPs, Se-TFPs exhibited significantly enhanced scavenging activity against 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), hydroxyl radicals, and superoxide anion radicals. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays, flow cytometry, and cell cycle apoptosis analysis revealed that Se-TFPs effectively inhibited MCF-7 cell proliferation at the S phase, with an IC50 value of 119.62 μg/mL.

Investigation of Aldoxime-Ketoxime Solvent Mixtures for Selective Copper Extraction: In-Depth Performance Evaluation Through RSM, Slope Method Mechanism Determination, Ex(%)-pH and McCabe-Thiele Diagrams

ABSTRACT Complexing agents are commonly employed as extractants for copper extraction, selectively removing copper while leaving other impurities in the aqueous phase. This study aims to optimize the combination of organic solvents in the solvent extraction process of copper when iron (II) impurity is present. Nine different organic solvents were investigated using experimental design and response surface methodology. The effects of ketoxime mole fraction (the mole ratio of ketoxime to the total amount of ketoxime and aldoxime), modifying agent concentration (%wt.), and temperature (°C) on the separation factor of copper and iron were examined for both extraction and stripping stages. Through extraction percentage versus pH diagrams, the organic solvent with a ketoxime mole fraction of 0.5 and a modifying agent concentration of 40% wt. demonstrated superior performance, yielding over 99% copper extraction and 10.40% iron extraction at pH 2.5 among the nine organic solvents. The slope analysis method determined an extraction number of 2 for the copper extraction process using all nine solvents. Additionally, McCabe-Thiele diagrams were employed to determine the number of stages required for solvents with favorable extraction conditions. Based on the findings, the organic solvent with a ketoxime mole fraction of 0.5 and a modifying agent concentration of 40% wt. achieved almost complete copper extraction with 2 extraction stages and 3 stripping stages.

Silicon-Based Sodium Hydride Core-Shell Structure for Portable Hydrolytic Hydrogen Generation.

Hydrogen production from silicon (Si) hydrolysis is environmentally friendly, safe, portable, and promising. However, the self-protected oxide layer around Si and a sluggish hydrolysis rate impede its practical utilization. To address this problem, we introduced sodium hydride (NaH) to form the core-shell structure of NaH/Si composites via a straightforward one-step, hand-mixing method in an ambient environment. NaH-based Si-M composites exhibit 83% hydrogen yield and a 52.7 mL/min hydrogen generation rate at 1-0.7 molar ratios. The hydrolytic activity includes the breakdown of NaH and the continuous hydrolysis of Si. X-ray diffraction, scanning electron microscopy, nanoindentation, and reaction observation studies have verified that NaH is pivotal in promoting thorough Si hydrolysis and attaining the maximum achievable yield compared to calcium hydride (CaH2). NaH/Si composites showed excellent hydrogen generation performance compared to CaH2/Si composites with microstructure silicon Si-S ≈ 1-3 μm, Si-M ≈ 75 μm, and Si-L ≈ 75-425 μm. Our study provided an innovative design and idea for utilizing cost-effective and easily transportable hydrogen production materials for practical applications, which has the potential for further advancement.

Use of deep eutectic solvents based on choline chloride, urea, and lactic acid as plasticizers in low‐density polyethylene films

AbstractThis study aims to investigate the performance of deep eutectic solvents (DESs) as plasticizers in low‐density polyethylene (LDPE) films and to compare them with di(2‐ethylhexyl) phthalate (DEHP). DESs were produced by mixing choline chloride with lactic acid and urea in 1:1 and 1:2 molar ratios. The prepared DESs were added to LDPE at two different ratios (10% and 30%), and films with 10 different compositions were produced by the extrusion method. The densities, viscosities, pH, volatility, and thermal values of the produced DESs were determined between 1.14 and 1.18 g/cm3, 22 and 99 mPa.s, 0.05 and 9.02, 0.7% and 18.9%, and <−70 and 63°C, respectively. When the DESs were examined in terms of their bond structure, it was observed that they could be produced successfully. The LDPE films with DES were characterized by thickness, mechanical, barrier, optical, DSC, FTIR, SEM, water behavior properties, heat sealability, and overall migration (OM) properties. According to the results of some basic analyses performed on the films, the first three films with the best properties (CL1:30, CL2:30, and DEHP:30) were determined using TOPSIS from the multi‐criteria decision hierarchy techniques. It was determined that the DES films with the most suitable properties had better properties than the control and DEHP films in terms of tensile strength (10–12 MPa), elongation at break (500%–545%), water vapor permeance (0.03–0.04 g/m2/h/kPa), and oxygen transmission rate (13–14 cm3/m2/day), water contact angle (>99°), and UV light barrier analyses. DES did not cause any change in the DSC and OM values of LDPE films. In general, important results were obtained regarding the use of DES as effective plasticizers in LDPE films.Highlights DES is a sustainable alternative to DEHP for LDPE plasticization. DES‐plasticized films showed 400% better elongation performance. DES‐plasticized films showed 25% better water vapor and 80% better oxygen barriers. DES‐plasticized films have superior UV light barrier and hydrophobic properties. DES‐plasticized films did not affect thermal stability or OM.

Thermodynamic and Structural Characterization of a Mechanochemically Synthesized Pyrazinamide–Acetylsalicylic–Acid Eutectic Mixture

Background/Objectives: This study aims to develop a sustainable and environmentally friendly drug delivery system by synthesizing a novel drug–drug eutectic mixture (DDEM) of acetylsalicylic acid (ASA) and pyrazinamide (PZA) using a green and efficient mechanochemical approach. Methods: The DDEM was characterized using various techniques, including differential scanning calorimetry (DSC), thermogravimetry and differential thermal analysis (TG-DTA), powder X-ray diffraction (PXRD), Fourier transform infrared spectroscopy (FT-IR), and Raman spectroscopy. Binary phase diagrams and Tammann’s triangle analysis determined the eutectic point. Density functional theory (DFT) calculations were performed on the starting compounds. The new system was evaluated for aqueous solubility, dissolution, and hygroscopicity. Results: A V-shaped binary phase diagram indicated the formation of a DDEM with a 2:1 molar ratio of ASA to PZA. A positive mixing enthalpy suggested a quasi-eutectic structure. The solubility of ASA and PZA increased by 61.5% and 85.8%, respectively, in the DDEM compared to the pure drugs. Conclusions: These findings highlight the potential of DDEMs to enhance drug properties and delivery. The synergistic interaction between ASA and PZA in the eutectic mixture may further improve therapeutic efficacy, warranting further investigation.

High‐Performance Mg–O2 Batteries Enabled by Electrospinning PVDF‐HFP‐Based Quasi‐Solid‐State Polymer Electrolyte

AbstractThis article reports a high‐performance rechargeable battery enabled by an electrospun quasi‐solid‐state electrolyte (E‐QSSE). The E‐QSSE, composed of Poly(vinylidene fluoride‐co‐hexafluoropropylene) (PVDF‐HFP), Mg(NO3)2 salt, and Pyr14TFSI ionic liquid (IL), exhibits high Mg2+ ion transport and interfacial stability. A unique sandwich structure coupling the E‐QSSE with a Ruthenium nanoparticles decorated multi‐walled carbon nanotubes (Ru/CNT) cathode catalyst on carbon paper significantly augments electrochemical reversibility. The optimized E‐QSSE with a 1:1 molar ratio of salt and IL achieves a high room temperature ionic conductivity of 6.39 mS cm−1. The E‐QSSE's electrochemical stability window extends up to 3.95 V, showcasing its potential for high‐energy‐density applications. The Mg‐O2 cell, with the optimized E‐QSSE, delivers 115 discharge/charge cycles at 100 mA g−1, one of the longest reported cycle‐lives for secondary Mg‐O2 batteries. The battery exhibits a maximum discharge capacity of 9305 mAh g−1 with 100% Coulombic efficiency. X‐ray photoelectron spectroscopy and absorption near‐edge structure analyses reveal MgO as the primary discharge product, with MgF2 contributing to stable solid electrolyte interphase. This E‐QSSE design promotes efficient Mg2+ ion migration and stable electrochemical reactions. This work advances the development of stable, high‐capacity Mg‐O2 batteries and can open up avenues for quasi‐solid‐state electrolytes in post‐lithium metal‐air battery technologies.

Effects of Extraction Temperature of Protein from Date Palm Pollen on the Astringency Taste of Tea

The astringency of tea, predominantly attributed to epigallocatechin gallate (EGCG), plays a crucial role in shaping its overall quality, and plant-based proteins are gaining popularity as a preferred alternative to milk-based proteins for enhancing the flavor profile of tea. This study investigated the impact of extraction temperature on date palm pollen (DPP) protein quality and tea astringency, comparing temperatures of 30 °C and 80 °C. Results indicated that higher extraction temperatures yield more protein and improve the thermal and surface properties of DPP. The molecular interaction between DPP and EGCG was investigated in an aqueous solution, and spectroscopic analyses (FTIR, UV, and CD) revealed that EGCG interactions at a 1:1 molar ratio induced structural changes in α-helix and β-sheet content in secondary structures in DPP, particularly at 80 °C, which strengthened and enhanced the hydrophobic interactions and hydrogen bonds between DPP molecules as EGCG concentration increased. A sensory evaluation using quantitative descriptive analysis (QDA) confirmed a significant reduction in astringency in DPP–tea polyphenol solutions extracted at 80 °C. This research highlights the potential of DPP as a functional ingredient in the food industry, creating a protein-polyphenol complex that reduces tea’s astringency while maintaining its unique flavor profile, thus offering a novel approach to enhance tea beverages.

Base-Promoted Regioselective Annulation of Pyridinium Ylides and Bromoalkynes for the Chemodivergent Synthesis of Indolizines.

A base-promoted regioselective formal [3 + 2] annulation of pyridinium ylides with bromoalkynes is reported, producing a series of substituent-diverse indolizines in generally good yields. A mild K2CO3-promoted three-component formal [3 + 2] cyclization of pyridinium ylides and bromoalkynes at a 2:1 molar ratio delivered C2-acylmethylated indolizines, whereas C2-brominated indolizines were generated starting from pyridinium ylides bearing strong electron-withdrawing groups at the pyridinium unit by using 2,2,6,6-tetramethyl-1-piperidinyloxy as a dehydrogenating reagent. The current synthetic methodology offers a controllable and modular approach to access indolizines with different substitution patterns, featuring a wide substrate scope, good functional group compatibility, and complete regioselectivity without the demand of any transition-metal catalysts.

Sulfidation of Magnetite for Superior Dechlorination of Trichloroethene.

The reported contributions of magnetite to the abiotic natural attenuation of chlorinated ethenes have generated interest in its potential for soil and groundwater remediation. In this study, we investigated the impact of the two-step sulfidation method on the physicochemical properties and reactivity of magnetite with trichloroethene (TCE). We systematically evaluated the effect of different sulfur precursors (dithionite, thiosulfate, and sulfide) and sulfur-to-iron ([S/Fe]dosed) molar ratios on the reactivity. Results were compared to those of sulfidated nZVI (S-nZVI) as a benchmark for assessing the efficacy of sulfidated magnetite (S-Fe3O4). The findings indicated limited reactivity of magnetite when sulfidated with dithionite and thiosulfate. However, sulfidation with sulfide yielded reaction rates comparable to those of S-nZVI, particularly at lower [S/Fe]dosed ratios. At higher [S/Fe]dosed ratios (>0.1), sulfide-sulfidated magnetite (S-Fe3O4_S) exhibited reaction rates surpassing those of S-nZVI, with the major dechlorination product being acetylene. Nonetheless, reusability experiments demonstrated that the performance of S-Fe3O4 diminished with aging. These results show that S-Fe3O4_S achieved complete transformation of TCE to acetylene, with reaction rates comparable to S-nZVI. Given its lower cost of production, engineered S-Fe3O4_S remediation systems could serve as a more affordable alternative for in situ chemical reduction of TCE with further research and development.

Synthesis and characterization of Co-W alloy coatings for enhanced hydrogen evolution: effects of bath composition and deposition parameters

This study explores the development of Co-W alloy coatings as efficient electrode materials for the hydrogen evolution reaction (HER), offering new insights into their performance. Using a specially formulated electrolyte bath with glycerol as an additive, Co-W alloy coatings were deposited on copper under different [Co2+]/[WO4 2−] molar ratios. Their electrocatalytic efficiency was evaluated in 1 M KOH through cyclic voltammetry (CV), chronopotentiometry (CP), and hydrogen gas measurements using a custom glass device. The results showed that the combination of Co and W in the coatings significantly enhances performance, as confirmed by SEM, XRD, and EDS analyses. Potentiodynamic polarization studies further explained the HER mechanisms. This work introduces a unique bath composition and demonstrates how optimizing the alloy composition can improve HER activity, paving the way for better electrocatalysts. The study identified that the Co-W coating prepared using a 0.35 M solution at a current density of 1 Adm2 demonstrated the highest electrocatalytic efficiency. This performance was attributed to the tungsten content of approximately 30 wt% and the maximum hydrogen evolution observed under these optimized conditions. The hydrogen evolution reaction (HER) in Co-W alloys follows the Volmer-Heyrovsky mechanism, characterized by the rapid evolution of hydrogen.

Optimization and kinetics of biodiesel production from Mesua ferrea oil using K2CO3 imbued on alumina nanocatalyst

The increasing scarcity of fossil fuels and rising geopolitical and environmental concerns have complicated energy production. Mesua ferrea linn seeds can be used to produce biodiesel as an alternative to conventional food crops. This study examined the catalytic activity of unsupported K2CO3 supported with alumina (K2CO3/Al2O3) in the transesterification reaction. The reaction was optimized using two methods: one variable at a time (OVAT) and Response Surface Methodology (RSM) with a Box-Behnken Design (BBD), which helped identify the linear and interactive effects of process variables on biodiesel yield. OVAT determined the optimal conditions to be: catalyst amount (6 wt%), methanol-to-oil molar ratio (6:1), temperature (60°C), time (60 min), and stirring speed (600 rpm). In contrast, RSM predicted the highest methyl ester conversion with: catalyst amount (6 wt%), methanol-to-oil ratio (7.8:1), temperature (55°C), and time (45 min). A confirmation experiment under RSM conditions achieved a maximum FAME conversion of 95.81%. RSM also indicated that the key parameters influencing transesterification, in order of significance, were temperature, time, and methanol-to-oil ratio. A pseudo-first-order kinetic model was also developed, revealing an activation energy of 53.95 kJ/mol.

Intranasal Mucoadhesive In Situ Gel of Glibenclamide-Loaded Bilosomes for Enhanced Therapeutic Drug Delivery to the Brain

Background: The neuroprotective efficacy of glibenclamide (GLIB) has been demonstrated in multiple rodent models of ischemia, hemorrhagic stroke, traumatic brain damage, spinal cord injury, and metastatic brain tumors. Due to its poor solubility, GLIB has low oral bioavailability, limiting its transportation to the brain via the oral route. Objectives: Here, we attempted to develop and optimize an intranasal mucoadhesive in situ gel of GLIB-loaded bilosomes using a 32 Box–Behnken design for brain drug delivery. Methods: To facilitate a longer residence time of the administered dose within the nasal cavity, the prepared bilosomes were loaded into a mucoadhesive in situ gel providing resistance to rapid mucociliary clearance. The amounts of sodium deoxycholate, the cholesterol/Span 40 mixture, and the molar ratio between the mixture’s components were chosen as independent variables, while the entrapment efficiency and in vitro drug release were selected as dependent variables. Results and conclusions: The optimal formulation was analyzed for particle size and entrapment efficiency, which were found to be 270.6 nm and 68.39%, respectively. In vitro drug release from optimal formulation after 12 h was 87.29 ± 1.98% as compared to 52.01 ± 2.04% of plain in situ gel of drug. An in vivo brain drug delivery study performed on Swiss albino mice showed that the brain concentration of drug through intranasal administration from mucoadhesive in situ gel of GLIB-bilosomes after 12 h was 2.12 ± 0.16 µg/mL as compared to 0.68 ± 0.04 µg/mL from plain in situ gel of drug. Conclusively, the developed bilosomal formulation offers a favorable intranasal substitute with enhanced therapeutic drug delivery to the brain.

Microstructural, magnetic, dielectric, and optical studies of La‐doped Sr2Fe0.5Hf1.5O6 double perovskite oxides

AbstractHerein, we report on the structural, magnetic, dielectric, and optical properties of La‐doped Sr2‐xLaxFe0.5Hf1.5O6 (SLFHO, 0.0 ≤ x ≤ 2.0) double perovskite oxides synthesized by solid‐state reaction method. X‐ray powder diffraction data and their Rietveld refinement reveal that the SLFHO powders crystallize in an orthorhombic structure with the Pnma space group. The SLFHO powders exhibit spherical morphology with an average particle size of 160 nm, as shown from SEM images. Their molar ratios of the Sr:La:Fe:Hf elements were determined as 1.77:0.50:0.50:1.95 by energy dispersive X‐ray spectroscopy data, approaching their nominal stoichiometry. X‐ray photoelectron spectra verified that Sr2+, La3+, Fe3+, and Hf4+ (Hfx+) ions existed in the SLFHO powders, and oxygen existed in species lattice oxygen and adsorbed oxygen, respectively. The SLFHO powders exhibit ferromagnetic behavior at 2 and 300 K, respectively, and at 2 K the saturated magnetization was 5.66 emu/g (or 0.60 μB/f.u.). Magnetic transition temperature, TC was determined to be 867 K. Dielectric measurements demonstrated a strong frequency‐dependent dielectric behavior observed in the SLFHO ceramics and a relaxor‐like dielectric behavior appearing in the temperature range of 200–600 K. Such relaxor‐like dielectric behavior is ascribed to the dielectric response of the singly‐ionized oxygen vacancies ( an activation energy of 0.54 eV. Room temperature optical properties of the SLFHO powders examined by using UV–vis diffuse reflectance spectroscopy exhibit high optical absorption in this wavelength region, and a wide indirect optical bandgap (Eg = 3.39 eV) was estimated using the Tauc's relation from the diffuse reflectance spectra. The SLFHO double perovskite oxides display high‐temperature ferrimagnetism, relaxor‐like dielectric behavior, and wide optical bandgap, making them potential to be employed in the fields of high‐temperature spintronics and magnetic semiconductor devices.

Characterization of Interpolyelectrolyte Complexes Based on Eudragit® RL and Oppositely Charged Eudragit® Polyanions as a Novel Matrix System for Colon-specific Drug Delivery.

The design of new interpolyelectrolyte complexes (IPEC) between Eudragit® polycation (type RL) and oppositely charged Eudragit® polyanions (types L100-55, L100, S100, FS) was investigated. The formation and chemical composition of novel IPECs between countercharged Eudragit® copolymers was established by gravimetric and elemental analysis. The structure and solid state properties of the synthesized IPEC were investigated comparatively to correspondent physical mixtures pairs of copolymers in similar molar ratio, using Fourier transform infrared (FTIR) spectroscopy and modulated temperature differential scanning calorimetry (mDSC). The binding ratio of a unit molecule of RL with polyanions was found to range between 1.73:1 and 4.19:1 while increasing the percentages of carboxylic groups in their structures from 10% (FS) to 50% (L100-55). As a result of electrostatic interaction between the copolymer chains, the glass transition temperature of the IPEC changed significantly. Considerable pH-sensitive swelling in acidic and neutral media was observed for different type of IPECs. Through evaluation of diffusion-transportation properties of the IPECs, basic mechanisms controlling the delivery of indomethacin were obtained. The results of swelling and release of the model drug from the polycomplex matrices confirm that they have potential to be used in colon-specific drug delivery.

Multifunctional Lanthanide Metal-Organic Frameworks Act as Fluorescent Probes for the Detection of Cr2O72-, Fe3+, and TNP, White Light-Emitting Diodes, and Luminescence Thermometers.

Two basically isostructural lanthanide-based metal-organic frameworks (Ln-MOFs), {[Eu(dptz)(H2O)2]Cl·3H2O}n (JLNU-10-Eu, JLNU = Jilin Normal University) and {[Tb(dptz)(NO3)(H2O)]·7H2O}n (JLNU-10-Tb), have been successfully synthesized by employing 3-(3,5-dicarboxylphenyl)-5-(pyrid-2-yl)-1H-1,2,4-triazole (H2dptz) as a flexible carboxylic acid ligand through solvothermal reactions. Single-crystal structural studies on Ln-MOFs manifested that the compounds have a two-dimensional (2D) layered structure. Furthermore, fluorescence sensing experiments indicated that JLNU-10-Eu and JLNU-10-Tb had significant fluorescence quenching effects on Cr2O72-, Fe3+, and TNP. It should be noted that the KSV value of JLNU-10-Eu in sensing Fe3+ could reach 7.36 × 103, and the limit of detection (LOD) was 0.57. The luminescence quenching mechanism is discussed in detail through some relevant experiments. Additionally, a series of Ln-MOFs, JLNU-10-EuxTb1-x (x = 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, and 0.1), have been obtained by simply regulating the molar ratio of Eu3+ and Tb3+. Particularly, JLNU-10-Eu0.8Tb0.2 can achieve white light emission at an excitation wavelength of 300 nm. The CIE coordinates are (0.316, 0.332), which are very approximate to ideal white light. JLNU-10-Eu0.2Tb0.8 as a luminescence thermometer exhibits good linearity over the temperature range of 303-373 K with a high sensitivity of 4.1% K-1 at 373 K. The construction of multifunctional Ln-MOFs displays prospective applications in fluorescent probes, white light-emitting diodes, and luminescence thermometers.

Oxidative Depolymerization of Lignin to Monophenolic Compounds Catalyzed by Spinel CuCo2O4

Lignin is the only natural polymer compound containing a benzene ring on earth, and its conversion to monophenolic compounds is attracting more attention. Cu‐dopped CuCo2O4 is synthesized and further used to catalyze the oxidative conversion of lignin to monophenolic compounds. It is found that the conversion of lignin is affected by the molar ratio of Cu to Co, the amounts of catalyst and H2O2, reaction temperature and time, and CuCo2O4 exhibits excellent catalytic performance. Under the optimized reaction conditions, the total yield of monophenolic compounds reaches 21.7%. CuCo2O4 also possesses good recyclable performance, and the total yield of monophenolic compounds slightly drops to 17.6% after four cycles. A plausible mechanism for the conversion of lignin to monophenolic compounds is proposed. During the depolymerization of lignin, CO and CC bonds are broken to form monophenols. This work provides an effective catalyst for the conversion of lignin to monophenol and expands the way of high‐value utilization of biomass.

Deciphering the Role of PEGylation on the Lipid Nanoparticle-Mediated mRNA Delivery to the Liver.

Organ- and cell-specific delivery of mRNA via modular lipid nanoparticles (LNPs) is promising in treating various diseases, but targeted cargo delivery is still very challenging. Most previous work focuses on screening ionizable and helper lipids to address the above issues. Here, we report the multifacial role of PEGylated lipids in manipulating LNP-mediated delivery of mRNA to the liver. We employed the typical excipients in LNP products, including DLin-MC3-DMA, DPSC, and cholesterol. Five types of PEGylated lipids were selected, and their molar ratio was fixed at 1.5% with a constant PEG molecular weight of 2000 Da. The architecture of steric lipids dramatically affected the in vitro gene transfection, in vivo blood clearance, liver deposition, and targeting of specific cells, all of which were closely linked to the de-PEGylation rate. The fast de-PEGylation resulted in short blood circulation and high accumulation in the liver. However, the ultrafast de-PEGylation enabled the deposition of more LNPs in Kupffer cells other than hepatocytes. Surprisingly, simply changing the terminal groups of PEGylated lipids from methoxyl to carboxyl or amine could dramatically increase the liver delivery of LNPs, which might be associated with the accelerated de-PEGylation rate and enhanced LNP-cell interaction. The current work highlights the importance of manipulating steric lipids in promoting mRNA delivery, offering an alternative approach for formulating and optimizing mRNA LNPs.