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Vitrimers are a class of polymers that combine the chemical and mechanical properties of traditional thermosets with the reshaping and reprocessing features of thermoplastics. Their reshaping ability is given by the presence of reversible bonds within their structure. While the nature of bonds that can ensure a dynamic behavior to the crosslinked network is well established, the challenge remains open to assess and control the reactivity of the system to rationally develop materials with desirable features in terms of processability and recyclability. In this work, a "free‐model" analysis of the curing reaction of an epoxy/anhydride resin in presence of zinc acetylacetonate as catalyst for both the curing reaction and transesterification is performed. Isothermal and non‐isothermal tests are conducted, and the data obtained are analyzed by means of isoconversional methods. The goal is to get an in‐depth insight into the reaction mechanism and the structure deriving from the crosslinked network formation, which can ultimately determine the material properties and eventually its actual reprocessability. [ABSTRACT FROM AUTHOR]

In this study, carboxymethyl locust bean gum was synthesized and nanocomposite hydrogel microspheres (GHMs) of gliclazide were produced based on nanosilicate reinforcement and aluminium-ion driven gelation process, followed by covalent crosslinking with glutaric anhydride (GA). The effect of three independent variables (polymer and GA concentration, incubation time) on the drug entrapment efficiency (DEE%) and percent drug release at 8 h, was optimized using Box-Behnken design. The highest DEE (%) and lowest drug release was achieved at the following optimized conditions: polymer (2.43 %), GA (0.34 %), and incubation (27 min). The nanoscilicate-enriched matrix provided a maximum of 75.13 % DEE, 92.33 % gel fraction, and excellent flowability. The optimized microspheres had virtually spherical morphology, according to FE-SEM analysis. FTIR study indicated a hydrogen bonding interaction between the drug and other formulation components. X-ray and DSC measurements suggested that the crystallinity of the drug decreased following integration into the matrix. The optimized GHM demonstrated anomalous diffusion of gliclazide in simulated gastrointestinal fluids for 12 h without disintegration. In streptozotocin (50 mg/kg BW)-induced diabetic rats, the optimized formulation diminished blood glucose level by about 72 % in 12 h. Thus, the nanocomposite GHMs created by combining nanosilicate with GA had an outstanding potential for long-term control of diabetes. [Display omitted] [ABSTRACT FROM AUTHOR]

In this study, through the cross-linking reaction of sulfosuccinic acid (SSA) and glutaric anhydride (GA) with polyvinyl alcohol (PVA), PVA/SSA/GA composite membranes were fabricated, and the effect of SSA content was investigated. The increase of SSA in the cation exchange membrane helps ameliorate the physical properties such as stress at break, elongation at break, and swelling behavior as well as cation exchange capacity. For the desalination test, PVA/SSA/GA composite solution was coated on the electrode, which exhibited enhanced performance compared to commercial ion exchange membrane. The fabricated membrane could also be utilized for 10 cycles of desalination process without any deterioration in the salt adsorption capacity, indicating that the PVA/SSA/GA membrane is a suitable candidate to be utilized in the MCDI systems. [ABSTRACT FROM AUTHOR]

The esterification of bagasse with glutaric anhydride could increase surface adhesion compatibility and the surface of derived polymers has the potential of immobilizing peptides or proteins for biomedical application. Due to its complicated components, the esterification mechanism of bagasse esterified with glutaric anhydride in ionic liquids has not been studied. In this paper, the homogenous esterification of bagasse with glutaric anhydride was comparatively investigated with the isolated cellulose, hemicelluloses, and lignin in 1-allyl-3-methylimidazolium chloride (AmimCl) to reveal the reaction mechanism. Fourier transform infrared (FT-IR) indicated that the three components (cellulose, hemicelluloses, and lignin) were all involved in the esterification. The percentage of substitution (PS) of bagasse was gradually improved with the increased dosage of glutaric anhydride (10-40 mmol/g), which was primarily attributed to the increased esterification of cellulose and hemicelluloses. However, the PS fluctuation of lignin led to a decrease in the PS of bagasse at high glutaric anhydride dosage (50 mmol/g). The esterification reactivity of bagasse components followed the order of lignin > hemicelluloses > cellulose. The esterification mechanism was proposed as a nucleophilic substitution reaction. Nuclear magnetic resonance (NMR) analysis indicated that lignin aliphatic hydroxyls were prior to be esterified, and primary hydroxyls were more reactive than secondary hydroxyls in cellulose and hemicelluloses. [ABSTRACT FROM AUTHOR]

Agar was modified with glutaric anhydride (GA) in this study to expand its application in food and medicine. Glutaric anhydride-modified agar (GAR) can maintain high gel strength (1247.4 g/cm2) and improved transparency (82.7 %). The esterified agar formed by GA further formed a cross-linking molecule structure by increasing the reaction temperature. Notably, excellent freeze-thaw stability (24.1 %) and swelling property (3116.6 %) of GAR indicated that the carboxyl-terminal of modified agar improves its affinity with water. Therefore, satisfactory water permeability and expansive stone enable agar films to achieve high water absorption. Furthermore, GAR films exhibit a specific absorption capacity of tetracycline hydrochloride in weak acid solution, thereby suggesting its potential application as a sustainable drug delivery carrier. Finally, the structure of the modified agar was analyzed to explain the mechanism of binding water. Cryo-scanning electron microscopy (SEM) depicted the porous structure of the agar gel responsible for swelling, drug loading, and release. Low-field NMR results showed that GA improves agar gel's binding and free water content. According to our research results, these GAR hydrogel membranes with excellent properties have the potential to be used as effective drug delivery materials. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Synthesis of Pseudo-Methionyl-Glutamate," by M. E. Dmitriev, A. V. Vinyukov, V. V. Ragulin, and N. F. Myasoedov published in the August 3, 2015 issue of the journal.

Rechargeable lithium metal batteries (LMBs) coupling with Ni-rich cathodes are promising high-energy-density electrochemical energy storage devices. However, the growth of Li dendrites and structural degradation of Ni-rich materials, associated with the erratic electrode-electrolyte interphase (EEI) and corrosion of harmful acidic species from the hydrolysis of LiPF 6 , seriously deteriorate the cycling performance of LMBs with Ni-rich cathodes. Herein, glutaric anhydride (GA) as a multifunctional electrolyte additive is proposed to achieve satisfactory lifespan of LMBs by in situ constructing LiNi 0.8 Co 0.1 Mn 0.1 O 2 (NCM811) cathode/Li anode-electrolyte interphases (CEI/AEI), and scavenging corrosive acidic species. The GA-derived CEI/AEI layers are rich in C O species, which can strongly coordinate with the Li anode and delithiated Ni-rich cathode surface. Thus, parasitic reactions of the electrolyte on the aggressive surface of the Ni-rich cathode and Li anode are notably reduced. Furthermore, the problems such as the inner microcrack evolution of NCM811 particles, the growth of Li dendrites and the corrosion of acidic species are well addressed. Consequently, the capacity retention of Li/NCM811 cell is increased from 59.4% to 90.7% after 300 cycles at 1C in the presence of GA, and the Li/Li symmetrical cell with GA exhibits the super-stable cyclic performance of 1400 h at 0.2 mA cm−2. [Display omitted] • The glutaric anhydride (GA) additive is cost-effective and environment-friendly. • GA-derived CEI/AEI films can effectively protect NCM811 cathode and Li-metal anode. • The detrimental effects of HF are alleviated by the hydrolysis reaction of GA. • The Li/NCM811 cell with GA delivers excellent cycling performance. • The Li/Li cell with GA can stably cycle for 1400 h at 0.2 mA cm−2. [ABSTRACT FROM AUTHOR]

Neutrophils are central players in the innate immune system. They generate neutrophil extracellular traps (NETs), which protect against invading pathogens but are also associated with the development of autoimmune and/or inflammatory diseases and thrombosis. Here, we report that lactoferrin, one of the components of NETs, translocated from the cytoplasm to the plasma membrane and markedly suppressed NETs release. Furthermore, exogenous lactoferrin shrunk the chromatin fibers found in released NETs, without affecting the generation of oxygen radicals, but this failed after chemical removal of the positive charge of lactoferrin, suggesting that charge-charge interactions between lactoferrin and NETs were required for this function. In a model of immune complex-induced NET formation in vivo, intravenous lactoferrin injection markedly reduced the extent of NET formation. These observations suggest that lactoferrin serves as an intrinsic inhibitor of NETs release into the circulation. Thus, lactoferrin may represent a therapeutic lead for controlling NETs release in autoimmune and/or inflammatory diseases.